Care must be taken not to encourage jurors to find contrary to facts known but not admissible

R. v. Butts, 2012 ONCA 24 cites R. v. Clarke (1981), 63 C.C.C. (2d) 224 with approval saying:

I recognize counsel's obligation to comment on nothing but the admissible evidence during closing submissions. But this responsibility should not be inverted to encourage jurors to make findings in conflict with undisputed facts which did not reach their attention simply because of trial safeguards.