04/30/2012 06:16 EDT | Updated 06/30/2012 05:12 EDT

Rafferty's lawyers face tough call

The Crown has wrapped its case against accused killer Michael Rafferty, but his defence team has not said whether he will testify — a decision legal experts say is one of the hardest lawyers face.

Rafferty, 31, has pleaded not guilty to first-degree murder, sexual assault causing bodily harm and kidnapping in the death of Victoria (Tori) Stafford, 8, who was abducted outside her school in Woodstock, Ont., on April 9, 2009. Her body was found in a farmer's field just southeast of Mount Forest, Ont., in July 2009

Under the Charter of Rights and Freedoms, the accused is presumed innocent and is not required to testify.

And that means a defence lawyer must weigh a number of elements before deciding whether the accused should step into the witness box, says Edward Greenspan, who has defended high-profile clients including Conrad Black and Karlheinz Schreiber.

One important consideration is whether the Crown has presented a strong case, because the prosecution must show beyond a reasonable doubt the accused has committed a crime, Greenspan told CBC News.

"If the Crown can't prove it, they can't prove it," Greenspan says, illustrating why sometimes there is no need to call the accused. On the other hand, he said, "if the conduct looks like if you don't call the accused they will convict — and the accused has an explanation — then you call them."

Saying too much or too little

An equally important consideration is the personality of the accused, Greenspan says, because how they act in the witness box will greatly influence how the jury perceives their version of events.

"Unfortunately, in a courtroom, a very honest person who is nervous and is upset and doesn't really know how to deal with questioning appears guilty," Greenspan says.

Likewise, he added, a person who is lying may seem completely believable if they are calm and collected.

Although the same can be said of any witness, "the accused is in the most difficult position because the jury is looking at them while the trial is going on and looking very closely," Greenspan says, noting nervousness may cause someone to say too much or too little, which can hurt their credibility.

One concern in not having an accused testify is that, for some, it makes the accused appear guilty, Greenspan says.

Can lead to 'worst-case scenario'

Leo Adler, a criminal defence lawyer with 37 years of experience, says most juries want to hear the accused say they "didn't do it."

According to the law, jurors are not to draw any inference from a person's decision to testify or not when considering the verdict. However, doing so opens up the accused to cross-examination, where Crown prosecutors can ask leading questions to undermine their credibility, Adler says.

"The worst-case scenario is in the cross-examination [the Crown] gets the accused to implicate himself," Adler says, while adding that the eliciting of an outright confession is extremely rare.

If a defence lawyer decides not to call the client, Adler says, it is best to mention several times over the course of the trial that it is the sole job of the Crown to show its case beyond a reasonable doubt.

"You have to work it into your closing to take away the sting of him not testifying," Adler said.

Along with the strength of the Crown's case, what the defence has planned affects whether to call an accused. A case in point, Adler says, are the proceedings in Florida against George Zimmerman, the man who fatally shot high school student Trayvon Martin, 17, in a case that made headlines in the United States and Canada.

In that type of case, Adler says, having an accused testify is important, because the defence wants to explain why an incident happened when the killing itself is not in doubt. That is quite different from a defence where an accused has denied all involvement in an alleged crime.

'One of the most difficult situations'

If he ultimately determines a client should go into the witness box, Greenspan says, he tries to have the accused answer every question the Crown is likely to ask through their testimony.

"In our system you're entitled to full disclosure of the Crown's case before the trial so you know what we call the 'case you have to meet,'" he said.

Determining whether an accused should testify involves balancing a host of competing considerations and every case is different, Greenspan says.

"It's one of the most difficult situations for any lawyer to be in."