That is correct, given the significant evidentiary burden that's placed on the accused—they need to call expert evidence—but also the test that they need to meet. They need to prove it on a balance of probabilities, which, in other words, means that they were more likely than not in a state of extreme intoxication at the time that the violence was committed. They need to prove it on a balance of probabilities, which is the most rigorous test that we have for raising a defence in the criminal law. It is considered to be quite an onerous test to meet. In that case, it could rarely be successful.
The other thing is that the former provision in section 33.1 has effectively prevented the defence from being successfully used since it was enacted in 1995, so we don't have a lot of data with respect to the defence over the last 20 years or so.