The Ontario Court of Appeal has ruled that the victim of an alleged sexual assault may not have to remove her niqab while testifying as long as the fairness of a trial is not compromised.Muslim Woman Wants to Appear Veiled in Canadian Court The World (Dec. 8, 2011):
The Supreme of Canada has heard the case of a Muslim woman who wants to appear veiled in court while she testifies against the two men she has accused of sexual assault.
The dynamic evidence page
Evidence marshaling software MarshalPlan
It's here: the law of evidence on Spindle Law. See also this post and this post.