[Trailerpark Badass]

"Reasonable doubt" can be created by attacking the state's evidence, and allows for any possible alternative theory, UNTIL the defense offers their own. The defense can offer its own evidence, things which it asserts ARE TRUE. That necessarily reduces the number of possibilities to two.

It's the defense that makes that choice.

[HiTech RedNeck]

There’s an excluded middle here: the defense can offer a range of possible occurrences. This is the lawyer speaking, and not the defendant himself speaking, of course.

[Tublecane]

“UNTIL the defense offers their own. The defense can offer its own evidence, things which it asserts ARE TRUE. That necessarily reduces the number of possibilities to two.”

That doesn’t sound right. You don’t have to choose either Casey killed her or she drowned and George helped cover it up. What if you don’t trust the case laid out by the defense or the prosecution? You still acquit. Maybe you think the defense was plausible but not accurate, and the prosecution plain wrong.

In any case, whatever the defense argues as an alternative theory you can ignore them and focus solely upon whether or not the prosecution proved guilt beyond a reasonable doubt. There’s nothing to say either you must believe their theory or the state’s.