A major debate last week in the ongoing Hassan Diab trial centered around whether Diab’s writing on his immigration papers matches the writing on a hotel registration card allegedly filled out by the bomber of a Paris synagogue in 1980.
Diab, a former Carleton sociology professor, is fighting extradition to France, where he is accused of being involved with the bombing.
The third – and latest – expert called forward by the defence, forensic document examiner Robert Radley, questioned the credibility of French expert Ann Bisotti.
Bisotti’s instructions for comparing the handwriting raise two important questions, Carleton criminology instructor Lawrence Buhagiar said in an email.
First, “did the judge’s instructions limit inappropriately the potential interpretations and conclusions?” Buhagiar wrote.
And second, “in following these instructions, did Ann Bisotti deviate from the accepted practice standards of graphologists who testify in legal proceedings?” he added.
These issues are a reminder that handwriting analysis is not an exact science, Buhagiar said. “Expert evidence is not a proxy for truth.”
Paulo Giancaterino, a Carleton law instructor and lawyer, agreed.
“If it’s reliable evidence that is able to be tested, it can bring a wealth of information to a trial,” Giancaterino said. “If it’s argued to be a prejudice part of the case, then it stops being useful.”
“You always have to be careful with novel sciences,” Giancaterino said, comparing handwriting analysis to DNA because they are both subjective factual opinions.
Another issue with the use of handwriting experts is the lack of a universal legal standard, Buhagiar said.
“The criticism becomes a ‘who would know better’ type of argument to undermine the credibility of those experts who do not agree with the conclusions reached by the French analysis,” he said.
In the end, “both sides could line up experts ‘til the cows come home,” Giancaterino said.
Crown attorneys have called into question the Skype conference call that all three defence experts participated in, according to a Jan. 8 story in the Ottawa Citizen.
Both Buhagiar and Giancaterino said they believe handwriting experts are important to a trial, but their reports must be taken lightly.
“At the heart of all evidence is a need to balance probative qualities – what it can tell us – against prejudicial qualities – how we might be biased by it,” Buhagiar said.
