''Do lawyers ask their clients if they have committed the crime?''

The question was posed by a caller during my interview of Dirk Derstine and Michael Edelson on my radio show on the weekend. Derstine had just finished defending Michael Rafferty and Edelson had represented Russell Williams.

There is a natural curiousity about the candid conversations lawyers have with their clients. All of the private communications are privileged and can never be disclosed by the lawyer. The questions posed by Dirk Derstine to Rafferty will forever be kept secret.

Do lawyers routinely ask their clients if they have committed the crimes alleged against them?

My own practice is to review any statements my client has given to the police in my initial interview. I will only conduct a thorough review of my client's position after I receive disclosure of the Crown's case against my client including police notes, witness statements, wiretaps, photographs and forensic evidence.

The disclosure provides me with an early snapshot of the strength of the Crown's case against my client. It allows me to begin building my client's defence to the charges. In some cases I will need to rely on my client's version where the defence presented is, for example, self-defence, alibi or consent. In other instances, my position may be that the Crown's case is weak and can't be proven beyond a reasonable doubt.

A lawyer-client interview is not a soul-searching confessional. The purpose of interviewing the client is to gather information that will be helpful in providing full answer and defence. In some instances, it will become apparent during the interview process that the client's goal is to resolve the matter and mitigate the sentence. In other cases, the evidence may appear overwhelming but the client's wish to contest the charges must be pursued fearlessly by counsel without equivocation.

The guiding principle is that the client is presumed innocent and the lawyer's professional obligation is to act as the client's advocate and not as judge and jury. There are professional limitations. The lawyer cannot knowingly call the client to testify and commit perjury. The lawyer is also prohibited from shaping the client's initial version into a defendable case. The classic scene in the 1959 film "Anatomy of a Murder" where the attorney portrayed by Jimmy Stewart rejected a series of defences suggested by his client until settling on an insanity plea was a clear example of unethical conduct by the lawyer.

We can be quite certain that in both the Rafferty and Williams case, defence counsel did determine their clients' positions about the charges they faced. In the Williams case, Michael Edelson's client pleaded guilty to two counts to first-degree murder and a series of other charges. Carefully drafted written instructions from Edelson's client would have been obtained prior to the plea. Russell Williams would be required to expressly acknowledge his guilt and complicity in his crimes in the instructions.

In the Rafferty trial, the cross-examination of the key witness, Terri-Lynne McClintic focused on Michael Rafferty being a horrified spectator to the killing of Tori Stafford by McClintic. McClintic rejected the suggestion and Rafferty never advanced his account in testimony before the jury. However, Dirk Dirstine couldn't have advanced this theory in cross-examination if it didn't follow his own client's version of events.

In the end, the secretive details of the lawyer-client communication will never be subjected to public scrutiny. The real issue is vigorous legal representation that serves the interests of justice. In the cases of Michael Rafferty and Russell Williams, this was notably achieved by all counsel.

Listen to Steven's new radio show, Closing Argument, every Sunday afternoon at 4:00ET on NewsTalk 1010. You can also follow him on Twitter at @LegalAnalyst