It was a question of fact in any given case what, if any, measures would be compatible with sufficient fairness of the trial. (newlawjournal.co.uk)
[80] To demonstrate an impairment of the right to make full answer and defence as a result of a default or delay in disclosure, an appellant must establish a reasonable possibility that the delayed or failed disclosure affected the outcome at trial or the overall fairness of the trial process: Dixon at para. 34; Stinchcombe at p. 348; R. v. C. (M. H.), 1991 CanLII 94 (S.C.C.), [1991] 1 S.C.R. 763, at p. 776. (slaw.ca)
The mother isn't defending her actions that led to her son's death but wonders about the fairness of the trial: (mommyish.com)