[circlecity]

No. The defendant merely has the burden of going forward with his affirmative defense to place the matter at issue. This can be him merely testifying that he was afraid for his life and safety. The ultimate burden rests with the state to disprove this. This is the same in any self defense case.

[nathanbedford]

You are perfectly right, that's the standard rule but I'm not so sure about every jurisdiction nor am I sure about particular bear cases which might be unique. So I took a look at perplexity:

It's important to note that some jurisdictions have slight variations. In a few places, the defendant might have to prove self-defense by a preponderance of the evidence (more likely than not), but the predominant rule, especially in the U.S.is that the prosecution bears the final burden to disprove self-defense once it's properly raised.

That is why I regretted not having access to the case.