COURT OF APPEAL FOR BRITISH COLUMBIA
R. v. Blais,
2008 BCCA 389
(Respondent on the application)
(Respondent on the application)
The Honourable Madam Justice Newbury
The Honourable Mr. Justice Low
The Honourable Mr. Justice Bauman
Counsel for the Appellant
E.A. Campbell and L. Ruzicka
Counsel for the Respondent,
R. Davies Q.C., and B.D. Vaze
Counsel for the Respondent,
Place and Date of Hearing:
Vancouver, British Columbia
17 June 2008
Place and Date of Judgment:
Vancouver, British Columbia
3 October 2008
Written Reasons by:
The Honourable Mr. Justice Bauman
Concurred in by:
Honourable Madam Justice Newbury
Reasons for Judgment of the Honourable Mr. Justice Bauman:
 Mr. Blais is charged with an offence under s. 213(1)(c) of the Criminal Code, R.S.C. 1985, c. C-46 (the "Code"), in relation to prostitution. That section provides:
(c) stops or attempts to stop any person or in any manner communicates or attempts to communicate with any person
for the purpose of engaging in prostitution or of obtaining the sexual services of a prostitute is guilty of an offence punishable on summary conviction.
 Mr. Blais was the alleged client in the incident. He wishes to advance a challenge to the constitutionality of the provision under ss. 2 and 7 of the Canadian Charter of Rights and Freedoms.
 In his counsel's Notice of Constitutional Question filed in Provincial Court, Mr. Blais gives notice of these arguments:
that i) Section 213 (1) (c) of the Criminal Code of Canada forbids communication of any kind between persons who have the right to communicate with one another for all legal purpose;
that ii) Sec 213 (1) (c) of the Criminal Code of Canada does not abate a nuisance but rather that it perpetrates within Canada a class of persons who are vulnerable to physical harm abuse and murder;
that iii) Sec 213 (1) (c) contributes to the physical harm, abuse and murder of the persons by suggesting that their lives and safety are less important than the nuisance purportedly caused by their engaging in street level prostitution.
[All errors in original.]
 Counsel argues, compendiously, that the section is "killing people". Mr. Blais hopes to lead the expert evidence of Dr. John Lowman, a professor in the School of Criminology at Simon Fraser University, in this regard.
 Dr. Lowman does not wish to testify in the Blais proceeding and he appeared before the Honourable Judge Angelomatis for an order quashing the subpoena ordering him to do so. The learned judge declined to vacate the subpoena. Dr. Lowman then brought certiorari proceedings in the Supreme Court of British Columbia to quash the subpoena. Madam Justice Gill allowed that application and Mr. Blais appeals from that decision to this Court.
 This case considers the proper approach to the exercise of the discretion to issue a subpoena under s. 698(1) of the Code where it is proposed to subpoena a person to give expert evidence in a proceeding to which that person has no ties and in which he or she is otherwise a complete stranger.
 In the certiorari proceedings, Dr. Lowman filed an affidavit setting out the background to the matter. No objection to supplementing the record in this manner was taken before Gill J. or this Court.
 Dr. Lowman deposes that he is currently working as an expert witness in superior court proceedings in Ontario and British Columbia in which Charter challenges to s. 213 are being advanced. Dr. Lowman is part of a large team of experts who apparently will give evidence touching various aspects of the complicated issues presented by prostitution in our society. He sets out the principal reasons for his reluctance to testify in the Blais proceeding at paras. 26-35:
26. There is an insufficient amount of time allocated to raise such a constitutional defence based upon my evidence. Initially, there was only half of a day allocated for that purpose. The evidence that Mr. Chouinard asked me to present, and now seeks to compel me to give, is complex and voluminous. My opinions are based upon thirty years of study. To be able to present that evidence in a clear and comprehensive manner to the court would require more than half of a day.
27. I am concerned that Mr. Chouinard, as counsel for the accused, will not be sufficiently knowledgeable of the issues, the evidence, or the data and methods used in my research. I mean no disrespect to Mr. Chouinard, but I do not believe that he appreciates the complexity of the issues. I am concerned that this could have a damaging impact on the interpretation of my research as it is presented to the court.
28. I do not want to give evidence in court on my research findings without sufficient time to prepare. Without adequate preparation I am very concerned that my evidence will be of little or no benefit to the court and I do not want to put my research, publications and academic integrity into evidence without being afforded proper time to prepare to defend my opinions and conclusions. I communicated my views on preparation to Mr. Chouinard and indicated that I would require at least five days to prepare. I do not have five days in the foreseeable future to dedicate to preparing for this trial.
29. If I am forced to testify at the trial I will have to make a choice between being unprepared or losing valuable time that is needed for other research and academic activities which are pressing. I am almost a year behind in completing a project that has been funded by the Social Science and Humanities Research Council grant. If I am forced to testify in the trial, it will cause me many inconveniences which I informed Mr. Chouinard I am not willing to agree to.
30. I informed Mr. Chouinard, in our various communications, that I did not believe that there is another expert who could be a standalone witness to provide the evidence he appears to be seeking. I also believe that by myself I will not be able to provide evidence sufficient to demonstrate to the court the facts necessary to successfully challenge section 213(c) of the Criminal Code. However, this does not mean that there are no other experts who can speak to these issues. In fact, I believe that several academics can provide similar evidence to the evidence Mr. Chouinard seeks to compel from me.
31. Part of my unwillingness to provide expert testimony in R. v. Blais, is based on the potential negative affect that it might have on the other actions in which I am a willing participant. If I am not prepared when I am compelled to give my evidence, if I am restricted due to the time allotted for the trial, or if Mr. Chouinard is unable to effectively make use of my evidence in direct examination, it may jeopardize the use of my evidence in the other actions by counsel in whom I have more confidence.
32. At no time did I enter into any form of agreement, written or oral, with Mr. Chouinard to be retained to provide expert evidence in the trial of R. v. Blais. To date, Mr. Chouinard has neither offered, nor have I accepted, any retainer moneys for my services. I have advised him that I would require payment for my services should I be forced to testify in R. v. Blais.
33. After early May, I did not have any further contact with Mr. Chouinard until mid to late July 2007 when I was served with a subpoena to attend court on October 10, 2007, in order to give evidence in the trial of Mr. Chouinard’s client. Attached as Exhibit “C” to this Affidavit is a true copy of the subpoena.
34. I understand that the subpoena was issued on July 5, 2007 by Judge Angelomatis. Attached as Exhibit “D” to this Affidavit is a copy of the transcript from the Provincial Court proceedings on July 5, 2007 in R. v. Blais. It is evident that Mr. Chouinard put before Judge Angelomatis a will-say statement containing a summary of the evidence that Mr. Chouinard claimed I would give. At no point did Mr. Chouinard consult with me in the preparation of that will-say statement, nor have I ever seen a copy of it.
35. I have also read Mr. Chouinard’s description of the ‘will say’ statement at p. 10, l. 36 to p. 13 l. 4 of that transcript. In it he seems to say that he is only going to ask me to confirm what I said to the House of Commons sub-committee on solicitation laws. In that presentation, which was an ‘invited submission’, I referred to B.C. wide homicide statistics that are assembled from newspaper reports, RCMP data and VPD data. Those statistics are important to my analysis, but form only a part of it; for my conclusions I depend on a much wider range of data, and a much broader analysis (essentially as summarised above, paragraphs 20-24), which is not found in my submission to the subcommittee. I expect that my evidence in the two constitutional challenges I am to testify in will include far more than the statistics in this presentation. Attached as Exhibit “E” to this affidavit is a copy of that presentation.
 Because of the then looming Provincial Court trial date, Madam Justice Gill was required to dispose of the application in a summary fashion late on a Friday evening. Her oral reasons for judgment were of necessity, brief. However, in them, she touched upon the principal issues which were argued at length before this Court. She noted that essentially three submissions were made on Dr. Lowman's behalf:
(1) that absent compelling necessity, an expert cannot be forced to provide opinion evidence if he or she does not wish to, at least in circumstances where, as here, the expert has no ties to the litigation or the matter in question;
(2) that under s. 698(1), both the materiality of the proposed evidence and the likelihood of the witness giving it must be established by the party seeking the subpoena and at least the latter has not been established here; and
(3) that in the circumstances it was not "in the interests of the administration of justice that Dr. Lowman be compelled to testify."
 With respect to the first submission, Gill J. concluded at paras. 8 and 10:
 As to arguments re compellability and necessity, I say first that I agree with the comments of Justice Cooke made in Seyfang v. G.D. Searle & Co.,  1 All ER 290, and of Justice Clarke who quotes those comments in Application of Forsyth; Re Cordova v. Philips Roxane Laboratories inc. (1984), 2 N.S.W.L.R. 327. Both justices were of the view that the English courts will not, as a general rule, require an expert to give expert evidence against his wishes in a case where he has no connection with the facts or the history of the matter in issue.
 On the issue of necessity, Dr. Lowman has clearly stated in his most recent affidavit that there are several academics who can provide similar evidence. Mr. Chouinard has challenged this, seemingly relying on Dr. Lowman’s response to an email some months ago in which he said he did not believe that there is another expert who could be a "standalone" witness to provide the evidence that Mr. Chouinard appears to be seeking. But Dr. Lowman does not believe that he could be that stand-alone witness either. Accordingly, necessity was neither considered nor has it been established.
 Gill J. also accepted Dr. Lowman's second submission (at para. 11):
 In respect of the next point, which is whether it is likely that the witness will give material evidence, Mr. Chouinard says that Dr. Lowman does not have conduct of the case and that it is not for Dr. Lowman or any other witness to determine what evidence is relevant or necessary. With respect, that submission misses the point. It is for Dr. Lowman to explain the basis of his opinion should he testify in any proceeding. Dr. Lowman says that his opinions are based upon 30 years of study. He describes the evidence as being complex and voluminous. If the approach of counsel does not allow Dr. Lowman to adequately present his evidence and the basis of his opinion, I do not even understand how it can be offered or why counsel would want to offer it. Mr. Chouinard said during argument that he did not know whether Dr. Lowman will stand by what is asserted in the will-say statement if he testifies. That alone says a great deal about the problem in the present matter.
 The learned judge did not find it necessary to opine on the third submission.
 It is implicit in the reasons of Gill J. that she found that the learned Provincial Court judge's decision to confirm the subpoena was made in excess of jurisdiction or based on an error of law on the face of the record.
 Counsel for Dr. Lowman opened his submissions in this Court by suggesting that there are three issues on this appeal and that success on any one of them would be sufficient to dispose of the appeal in Dr. Lowman's favour. Counsel frames the three issues as follows:
(1) whether an expert with no personal connection to the facts of the case can be compelled to testify in that case;
(2) whether the Provincial Court judge failed to apply the test under the Criminal Code for the issuance of a subpoena; and
(3) whether ultimately the issuance of a subpoena is discretionary; that is, if Dr. Lowman is compellable and if he is likely to give material evidence, may the court consider whether it is in the best interests of the administration of justice for the subpoena to issue?
 Much time is spent in Dr. Lowman's factum on the first issue and counsel concludes his submission on it by urging the adoption of a general rule that the court will not require an expert to give evidence against his wishes in a case where he has no connection with the facts or the history of the matter in issue.
 The alternative, submits counsel, is a rule to the effect that an expert is prima facie compellable regardless of her personal interests in the matter, subject to the court's discretion in a proper case to release her from testifying.
 Gill J., in her oral reasons, adopted the general rule urged by Dr. Lowman's counsel, which in turn is based on the judgment of Cooke J. in Seyfang v. G.D. Searle and Co. and Another,  1 Q.B. 148,  1 All E.R. 290.
 In my view, it is not correct to consider such a general rule in a vacuum, divorced from the context of the power to issue the subpoena in question.
 In the case of the criminal law, the subpoena power has a statutory foundation in respect of the accused's ability to compel the attendance of witnesses. At common law, at least until the mid-17th century, an accused was not permitted to have witnesses. In criminal actions, the first English statute providing for the compulsion of witnesses was in 1695: An Act for Regulating Trials in Cases of Treason and Misprision of Treason, 7 & 8 Will. III, c. 3, s. 7.
 It is necessary, then, to consider the scope of the subpoena power in the context of the statutory power which creates it, here s. 698 of the Code:
698. (1) Where a person is likely to give material evidence in a proceeding to which this Act applies, a subpoena may be issued in accordance with this Part requiring that person to attend to give evidence.
(2) Where it is made to appear that a person who is likely to give material evidence
(a) will not attend in response to a subpoena if a subpoena is issued, or
(b) is evading service of a subpoena,
a court, justice or provincial court judge having power to issue a subpoena to require the attendance of that person to give evidence may issue a warrant in Form 17 to cause that person to be arrested and to be brought to give evidence.
(3) Except where paragraph (2)(a) applies, a warrant in Form 17 shall not be issued unless a subpoena has first been issued.
 Mr. Justice Watt (then of the Ontario Superior Court) recently considered s. 698 in R. v. Baltovich [Finkle v. Ontario],  O.J. No. 3506 (Sup. Ct. J.) (QL), and made some elementary observations which I respectfully adopt. In particular at paras. 58 and 59 the learned judge stated:
58 Section 698(1) sets the threshold for issuance of the subpoena…. The issuer must be satisfied that the proposed witness is likely to give material evidence. But the subsection offers no assistance about the manner in which the party requesting the subpoena is to satisfy that threshold for its issuance.
59 A final preliminary observation about the issuing authority of section 698(1) is apt. The subsection is cast in permissive terms: The permissive “may” is used, not the imperative “shall”. In the result, satisfaction of the statutory threshold does not guarantee issuance of the subpoena.
[Emphasis in original.]
 As to the manner of satisfying the threshold test, Watt J. referred to Chief Justice Bayda's discussion in Foley et al. v. Gares (1989), 53 C.C.C. (3d) 82 (Sask. C.A.) at 88:
What type of inquiry is a justice acting under ss. 626 [now s. 698(1)] and 627(2)(a) [now s. 699(2)(a)] required to make? It is safe to say that the standard of inquiry is not so high, for example, as that expected of a judge acting under s. 627(3) [now s. 699(3)], but the justice none the less should make some examination of the circumstances. He is given discretion in the matter of issuing the subpoena and he should exercise it judiciously if not judicially. The justice may choose not to insist upon evidence on oath but he may want to conduct an oral examination, if only a cursory one, of some person who has knowledge of the circumstances. The extent of such an examination will depend on the circumstances of each situation. One thing however is certain. If he takes no steps whatever to satisfy himself that the person is likely to give material evidence, the justice is abusing his power and his discretion if he issues the subpoena. His decision to issue the subpoena may be set aside by a superior court on the ground that without making any examination the justice had no jurisdiction to exercise his discretion to issue the subpoena. In short his decision is amenable to certiorari.
 Watt J. then turned to discuss the standard of "likely to give material evidence". He said (at paras. 70-72):
70 The statutory terms “is likely to give material evidence” refers to a probability, not a mere possibility or something that exists only in the fevered imaginings of the party seeking the subpoena. Something is likely if it is probable, not merely possible.
71 Materiality is a legal concept. It defines the status of the propositions that a party seeks to establish by evidence to the case at large. What is in issue in a case, hence what is material, is a function of:
i. the applicable substantive law;
ii. the allegations contained in the indictment; and
iii. the applicable procedural law.
Evidence is material if it is offered and tends to prove or disprove a fact in issue. Material evidence is evidence that is pertinent to the issue in dispute.
72 When the issuance of a subpoena is challenged, it is inadequate for the party proposing to call the witness, in this case the prosecutor, to respond with a mere allegation that the proposed witness can give material evidence. More is required. And that more is to establish that the proposed witness is likely, or said another way, would probably have evidence material to the issues raised to give. See, R. v. Harris (1994), 93 C.C.C. (3d) 478, 479-80 (Ont. C.A.). See also Re Stupp and The Queen (1982), 36 O.R. (2d) 206, 70 C.C.C. (2d) 107, 121 (H.C.J.) per Craig J.
[Emphasis in original.]
 So, we are left with the initial observation of Mr. Justice Watt that, s. 698(1) above all creates a discretion and "in the result, satisfaction of the statutory threshold does not guarantee issuance of the subpoena."
 What considerations ought properly to guide the exercise of that discretion? It is here, in my view, that considerations of a proposed expert's lack of connection to the case, and his or her unwillingness to testify in it, are to be weighed.
 I turn to discuss the cases on this issue.
 Counsel have been very diligent in their research on the law. There is little Canadian jurisprudence considering the compellability of an expert who is totally unconnected to the proceedings. United Kingdom and Australian authorities are accordingly of assistance. I will refer below to these: Harmony Shipping Co. SA v. Davis,  3 All E.R. 177 (C.A.); Seyfang, supra; Society of Lloyd's v. Clementson (21 February 1996), England (C.A.); Re Application of Forsyth,  2 N.S.W.L.R. 327 (S.C.); Witness v. Marsden, 2000 NSWCA 52.
 Harmony Shipping Co. SA is a leading case cited and followed by many Canadian courts, including this Court. This portion of the headnote sets out the facts and the disposition at trial:
A handwriting expert, one of only a few such experts, was approached by the plaintiffs in an action to advise on the authenticity of a document, the genuineness of which was crucial to their case. The expert advised that the document was not genuine. In discussing his fee for the advice the expert stated that it was a rule of his not to give advice to both sides in an action. Subsequently the expert was approached by the defendants to the action to advise them of the document's authenticity. Not realising that he had already advised the plaintiffs on the matter, he advised the defendants that the document was not genuine. He later realised that he had advised both sides and told the defendants that he could accept no further instructions from them. The defendants, who wished the expert to give evidence on their behalf, issued a subpoena ad testificandum requiring him to attend and give such evidence. The plaintiffs applied to the trial judge to set aside the subpoena but the judge ruled that the expert was a compellable witness and ought to give evidence as to his opinion of the document.
 The appeal was dismissed. Lord Denning M.R. characterized the issue before the court in this way (at p. 180h):
So we have before us a question of principle. If an expert witness has been consulted by one side and has given his opinion to that side, can he thereafter be consulted and subpoenaed by the other side to give his opinion on the facts of the case? That is the issue which this court has to decide.
 I note here that the issue before the court in Harmony Shipping Co. SA was not what is precisely the case before us. There the expert had already expressed the opinion in respect of which he was to be compelled to testify. Here the expert has no previous involvement with the litigants and he has not yet expressed the precise opinion sought of him in the prosecution.
 Lord Denning first made these observations as to the compellability (and the rationale therefor) of witnesses of fact (at p. 180-81):
So far as witnesses of fact are concerned, the law is as plain as can be. There is no property in a witness. The reason is because the court has a right to every man’s evidence. Its primary duty is to ascertain the truth. Neither one side nor the other can debar the court from ascertaining the truth either by seeing a witness beforehand or by purchasing his evidence or by making communication to him. In no way can one side prohibit the other side from seeing a witness of fact, from getting the facts from him and from calling him to give evidence or from issuing him with a subpoena. That was laid down by the Law Society in their Guide to the Professional Conduct of Solicitors in 1944 [footnote omitted]. It was affirmed and approved in 1963 by Lord Parker CJ and the judges. It is published in the Law Society’s Gazette for February 1963. It says [footnote omitted]:
‘...the Council have always held the view that there is no property in a witness and that so long as there is no question of tampering with the evidence of witnesses it is open to the solicitor for either party in civil or criminal proceedings to interview and take a statement from any witness or prospective witness at any stage in the proceedings, whether or not that witness has been interviewed or called as a witness by the other party.’
That principle is established in the case of a witness of fact: for the plain, simple reason that the primary duty of the court is to ascertain the truth by the best evidence available. Any witness who has seen the facts or who knows the facts can be compelled to assist the court and should assist the court by giving that evidence.
 The learned judge considered whether that principle applied in the case of an expert witness. Lord Denning stated that to the extent communications between the solicitor and the expert were privileged, no questions could be asked of the compelled expert but (at p. 181):
Subject to that qualification, it seems to me that an expert witness falls into the same position as a witness of fact. The court is entitled, in order to ascertain the truth, to have the actual facts which he has observed adduced before it and to have his independent opinion on those facts. It is interesting to see that it was so held in Canada in MacDonald Construction Co Ltd v. Lathe & Plastering Co Ltd [(1972), 27 D.L.R. (3d) 253 (N.S.S.C.)]. In this particular case the court is entitled to have before it the documents in question and it is entitled to have the independent opinion of the expert witness on those documents and on those facts, excluding, as I have said, any of the other communications which passed when the expert witness was being instructed or employed by the other side. Subject to that exception, it seems to me (and I would agree with the judge on this) that the expert witness is in the same position when he is speaking as to the facts he has observed and is giving his own independent opinion on them, no matter by which side he is instructed.
 I emphasize again that this was a case of an expert with ties already to the case there at bar. Indeed, as Lord Denning notes, the witness there had observed "actual facts" i.e. he had already viewed the impugned document.
 Both Lord Justices Waller and Cumming-Bruce agreed with Lord Denning. Cumming-Bruce L.J. stressed the uniqueness of the case (at p. 184):
I would only add that the different kinds of expert witness are various, and this case is concerned with the particular functions, responsibilities and activities of a handwriting expert, and the problems raised by the case arise from very unusual and peculiar facts.
 Seyfang, unlike Harmony Shipping Co. SA, was a case involving experts with no previous ties to the litigation in which they were to be compelled to testify. There, American parties involved in a U.S. pharmaceutical product liability claim sought an English court order compelling certain U.K. experts to testify in the U.S. litigation pursuant to letters rogatory issued by a U.S. court.
 Mr. Justice Cooke related the experts' background on the issues before the U.S. court at p. 150 and at p. 152 concluded that the law to be applied on the application was the same as that "which the English courts apply to the calling and examination of witnesses in proceedings initiated in the courts of this country". Cooke J. then formulated this principle (at p. 152):
… English courts will not as a general rule require an expert to give expert evidence against his wishes in a case where he has had no connection with the facts or the history of the matter in issue. That principle will apply with particular force where the expert cannot give the evidence required of him without a breach of confidence, and where the preparation of the evidence required of him would require considerable time and study. This … principle, if it be correct, establishes a distinction between expert evidence and evidence as to matters of fact. The distinction is relevant in determining how the courts should exercise their discretion under section 1 of the Act of 1856. It would be equally relevant in determining whether the court should set aside a subpoena issued in proceedings in this country.
In the result he set aside the order requiring the experts to testify.
 Seyfang was considered and applied in the Queen's Bench Division by Mr. Justice Kerr in Lively Ltd. v. City of Munich,  1 Lloyd's Rep. 418. He applied the above principle articulated by Cooke J. and added (at p. 419):
… There are many reasons why experts should generally not be compelled to appear as witnesses in proceedings against their wishes if the evidence can be obtained elsewhere and if they have not been concerned in the matter professionally or in any other way.
 Both cases were considered by the English Court of Appeal in Society of Lloyd's v. Clementson (21 February 1996), England (C.A.). There, Staughton L.J. noted that both Seyfang and Lively Ltd. had been cited in argument in Harmony Shipping Co. SA. The learned judge concluded (at p. 3-4):
In my judgment the court has a discretion in the case of an expert, whether or not it has any discretion in the case of a witness of fact. It will take into account (i) that the court is prima facie entitled to every man’s evidence, whether of fact or opinion; (ii) whether the expert has some connection with the case in question; (iii) whether he is willing to come, provided that his image is protected by the issue of a subpoena; (iv) whether attendance at court will disrupt or impede other important work that he has to do; and (v) whether another expert of equal calibre is available. There may well be other relevant considerations. In particular, it is fairly arguable that an officer or employee of one party should not be called as an expert by the other unless that is necessary for justice to be done.
 Of note is the fact that Staughton L.J. did not characterize the general rule as did the judges in Seyfang and Lively Ltd. He held that the general rule is that the court is entitled to every man's evidence but enjoys a discretion in the case of an expert to excuse him or her. He highlighted some of the considerations guiding the exercise of that discretion.
 Henry L.J. agreed with Staughton L.J. and stated (at p. 5):
Subject to the above I am of opinion that Seyfang v. Searle,  1 QB 148,  1 All ER 290 remains good authority for the proposition that when it comes to setting aside a subpoena a distinction, at any rate in the exercise of the court’s discretion, should be made between expert witnesses and witnesses of fact. That case, dealing as it was with the position of what I might describe as the conventional independent expert who gives evidence as part of his profession, is not exhaustive in the principles it lays down. Nor should it be construed as a statute.
 Again, this speaks to the general rule being that of compellability with the discretion to excuse.
 Seyfang was considered by the Supreme Court of New South Wales in Re Application of Forsythe; re Cordova v. Philips Roxane Laboratories Inc.,  2 N.S.W.L.R. 327 (S.C.). Clarke J. noted the "general rule" stated in Seyfang and Kerr J.'s adoption of it in Lively Ltd. (at p. 335):
In view of the support afforded Seyfang by Kerr LJ, as he now is, and the manner in which the common law has developed in this State, I am not prepared to conclude that Cooke J was in error, nor that the rule of practice does not apply in New South Wales. It seems to me that the rule is based on sound commonsense and enables experts to protect themselves against being drawn into litigation in which they have no concern and against their will. After all, it is not an absolute rule and not every application by an expert to set aside a subpoena will necessarily succeed. It is a general rule which carries significant weight in a determination of the appropriate exercise of a discretion. Interestingly enough, those who conduct litigation in the State of California will not be unfamiliar with the rule. The Court of Appeals in that State in Agnew v Parks 172 Cal App 2d, 756 at 763, 764, held that a doctor who had no relationship with a patient was not a compellable expert witness in proceedings brought by that patient.
 Seyfang, Lively Ltd. and Forsythe were referred to in Witness v. Marsden, 2000 NSWCA 52 (at para. 59). Those cases were in Heydon J.A.'s view "a special illustration of the power of the court to set aside process in the nature of a subpoena … in relation to experts" (at para. 59).
 In my view, in a criminal law context, it would not be appropriate to adopt the general rule as set out in Seyfang. The formulation of the discretion to compel the attendance of an expert in such circumstances, stated by Staughton L.J. in Clementson and extracted above, is more in keeping with the discretion created by s. 698 of the Criminal Code and the important consideration that the accused is entitled to make full answer and defence.
 While Crown counsel acknowledges that there may be situations in which a court will refuse to issue a subpoena under s. 698, even where a witness has material evidence to give, she goes on to submit, correctly in my view, that this should be the exception rather than the rule. Counsel cites in support J.H. Wigmore, Evidence in Trials at Common Law, Vol. 8 (McNaughton rev. 1961), para. 2192 at p. 70:
For more than three centuries it has now been recognized as a fundamental maxim that the public (in the words sanctioned by Lord Hardwicke) has a right to every man’s evidence. When we come to examine the various claims of exemption, we start with the primary assumption that there is a general duty to give what testimony one is capable of giving and that any exemptions which may exist are distinctly exceptional being so many derogations from a positive general rule.
 In summary, then, in the case of compelling an expert's attendance at trial under s. 698, having established that he or she is likely to give material evidence in the proceeding, the issuing judge or justice should further consider, at least, these matters:
(i) the prima facie entitlement of the court to every person's evidence, whether of fact or opinion;
(ii) whether the expert has some connection with the case in question;
(iii) whether the expert is willing to come "provided his image is protected by the issue of a subpoena";
(iv) whether attendance at court will disrupt or impede other important work that the expert has to do;
(v) whether, and to what extent, the expert will be required to expend time and effort in preparing evidence for the court; and
(vi) whether another expert of equal calibre is available.
This list is not exhaustive.
 Looking at Dr. Lowman's list of concerns set out in his affidavit, I do not accept that the following are proper considerations in the exercise of the judicial officer's discretion:
· the concern with defence counsel's competence to effectively advance the expert's thesis; and
· the concern that the expert's testimony in the case in question will have a negative affect "on other actions in which I am a willing participant".
 Crown counsel at para. 28 of her factum addresses a further concern:
In her Reasons, it appears that the learned Hearing Judge in the case at bar considered two questions: (1) whether Dr. Lowman is likely to give material evidence; and (2) whether the Appellant has demonstrated the necessity of Dr. Lowman’s evidence (i.e. were there alternate sources or witnesses from whom the Appellant could obtain this evidence). From a review of the relevant Canadian criminal jurisprudence, a demonstration of “necessity” only appears to have arisen under s. 698 where a party is seeking to subpoena either (1) a media outlet or journalist: R. v. Baltovich, [ O.J. No. 3506 (Ont. S.C.J.)] at paras. 79, 90-92; R. v. Hughes, [ B.C.J. No. 1694 (S.C.)] at paras. 56-66; or (2) prosecuting Crown counsel or defence counsel of record: R. v. Elliott [(2003), 181 C.C.C. (3d) 118 (Ont. C.A.)], at paras. 114-119; R. v. Colbourne (2001), 157 C.C.C. (3d) 273 (Ont. C.A.); R. v. Brown,  O.J. No. 6163 (Ont. Gen. Div.) at para. 12; R. v. Chenier,  O.J. No. 1279 (Ont. S.C.J.) at paras. 6 and 7; R. v. Chan,  A.J. No. 1315 (Alta. Q.B.) at paras. 10-15; R. v. Polo,  A.J. No. 354 (Alta. Q.B.) at paras. 49-52.
[Emphasis in original.]
 It is not completely clear to me that Madam Justice Gill, in her necessarily brief oral reasons, was requiring the subpoena's proponent to establish on a balance of probabilities the necessity of Dr. Lowman's evidence. It may only be the case that she considered necessity, or the availability of alternate witnesses and the apparent lack of reference thereto by the Provincial Court judge, as a matter going to the exercise of the residual discretion under s. 698. In that regard, it is a relevant consideration in deciding ultimately whether to compel the reluctant expert who is before the court.
 That is not to say, however, that necessity is something which the proponent need demonstrate on a balance of probabilities in order to obtain a subpoena in respect of this class of witness. As Crown counsel points out, that burden has only been imposed in a narrow class of cases and I would not extend it to the circumstances of the expert at bar.
 It remains to consider the appeal in light of these considerations.
 As discussed above, the standard of review to be applied by Gill J. was whether the Provincial Court judge had acted in excess of jurisdiction or made an error of law on the face of the record in issuing the subpoena and refusing to vacate it. Mr. Blais submits that Gill J. did not apply the appropriate standard of review and instead conducted a re-hearing.
 This appeal is brought pursuant to s. 784 of the Criminal Code and Part XXI of the Code applies to appeals brought under that section. Section 686 of that part delineates the powers of the Court of Appeal. Pursuant to s. 686(1)(a)(ii), this Court may allow the appeal if the hearing judge made a wrong decision on a question of law.
 I have already discussed my disagreement with the adoption of the general rule in Seyfang in a criminal law context. However, it is, as well, implicit in the reasons of the hearing judge, if not express, that she concluded that the learned Provincial Court judge did not address the threshold question on the s. 698 application, viz., whether the accused had demonstrated that Dr. Lowman "is likely to give material evidence". As I read the learned hearing judge's reasons, she implicitly concluded that the Provincial Court judge had not addressed that issue because the record before him was clearly deficient in that regard, as Gill J. details in para. 11 of her reasons.
 In his reasons of 23 October 2007 refusing to vacate the subpoena, Judge Angelomatis discussed the concept of material evidence in para. 1.
 In para. 2, the learned judge adverted to defence counsel's assertion that Dr. Lowman's "decades of study of prostitution … will go towards augmenting and proving or disproving the Crown's case". He then concluded:
 I have no reason to reject Mr. Chouinard’s assertion, the nature of the charge, soliciting for the purpose of prostitution, the studies done by Dr. Lowman on the face of it all, to my mind, establish beyond a reasonable - I do not have to go beyond a reasonable doubt, but overwhelmingly suggest to me - that it is material evidence. So the subpoena will remain in force.
 Thus, while the issuing judge considered the materiality of the evidence which Dr. Lowman might be able to give, he did not ask himself the critical question: is Dr. Lowman likely to give material evidence? That is the issue addressed by Gill J. in para. 11 of her reasons, although her conclusion, that Dr. Lowman likely would not in the circumstances, could have been more clearly stated.
 I see no error in the hearing judge's conclusion on this issue. I have already noted Foley and its discussion of the manner in which the inquiry under s. 698 is to be conducted. As Chief Justice Bayda stated (at p. 88) of the issuing judge:
… One thing however is certain. If he takes no steps whatever to satisfy himself that the person is likely to give material evidence, the justice is abusing his power and his discretion if he issues the subpoena. His decision to issue the subpoena may be set aside by a superior court on the ground that without making any examination the justice had no jurisdiction to exercise his discretion to issue the subpoena. In short his decision is amenable to certiorari.
 I note, as well, that quite apart from this conclusion, it is also clear that the Provincial Court judge did not address the residual discretion not to issue the subpoena in light of the considerations I have earlier discussed.
 I would dismiss the appeal.
“The Honourable Mr. Justice Bauman”
“The Honourable Madam Justice Newbury”
“The Honourable Mr. Justice Low”