R v Jalili, 2018 ONSC 6408 (Akhtar):

[42] In R. v. Babos, 2014 SCC 16, [2014] 1 S.C.R. 309, the Supreme Court of Canada acknowledged that a stay of proceedings is the most drastic remedy that a court can order. The court, at para. 31, identified two categories of cases where a stay of proceedings would be justified:
(1) where state conduct compromises the fairness of a trial (“the main category”)
and
(2) where state conduct creates no threat to trial fairness but risks undermining the integrity of the judicial process (“the residual category”)

[43] At para. 32, the court outlined the test to be used to determine whether to impose a stay. The test consists of three requirements:
(1) There must be prejudice to the accused’s right to a fair trial or the integrity of the justice system that will be manifested, perpetuated or aggravated through the conduct of the trial, or by its outcome;
(2) There must be no alternative remedy capable of redressing the prejudice; and
(3) Where there is still uncertainty over whether a stay is warranted after steps (1) and (2), the court is required to balance the interests in favour of granting a stay, such as denouncing misconduct and preserving the integrity of the justice system, against the interest that society has in having a final decision on the merits.

[44] The lack of alternative remedy requirement under the second part of the test followed R. v. O’Connor, [1995] 4 S.C.R. 411, at p. 466, where the court stated that a stay of proceedings in non-disclosure cases “is a last resort, to be taken when all other acceptable avenues of protecting the accused’s right to full answer and defence are exhausted.” The court concluded, at p. 468:
Where life, liberty or security of the person is engaged in a judicial proceeding,
and it is proved on a balance of probabilities that the Crown’s failure to make
proper disclosure to the defence has impaired the accused’s ability to make full
answer and defence, a violation of s. 7 will have been made out. In such
circumstances, the court must fashion a just and appropriate remedy, pursuant to
s. 24(1). Although the remedy for such a violation will typically be a disclosure
order and adjournment, there may be some extreme cases where the prejudice to
the accused’s ability to make full answer and defence or to the integrity of the
justice system is irremediable. In those “clearest of cases”, a stay of proceedings
will be appropriate.