It is really sad that it took over 30 years and the person is still working, albeit in Israel. But wouldn't the Evidence Act(provincial and federal) set the standards that allowed this?

The Evidence Act can further restrain the court but in a scenario that is ambiguous the court will rely on case law (e.g. law the court itself made up based on prior decisions). Should parliament disagree with the decisions of the court they may amend the law to force a change in future trials.

We're used to hearing about the supreme court restraining the actions of parliament by declaring something unconstitutional but in actuality the parliament exercises far more control over the court than vice versa. Even in the case of the court declaring something unconstitutional parliament could overrule them by changing the constitution itself (although that is extremely unlikely given the political climate).