>Perhaps in another jurisdiction, but not in the US you can't.
Yes you can. Even if there are rules banning it, like any system made by humans, exceptions are made when they are popular enough (or when the target is unpopular enough). In the US in particular, the way exceptions are made is to consider the punishments not being punishments. So while this does mean that extra prison time can't be used, things like indefinite involuntary commitment or extensions of no punishment actions are allowed. One example is extensions of time on the SOR, which has been ruled to not violate ex post facto even when the extension happens after the sentence has been given.
As I said, we can and we do. We just play creatively at it so we can pretend we don't violate ex post facto.
Yes you can. Even if there are rules banning it, like any system made by humans, exceptions are made when they are popular enough (or when the target is unpopular enough). In the US in particular, the way exceptions are made is to consider the punishments not being punishments. So while this does mean that extra prison time can't be used, things like indefinite involuntary commitment or extensions of no punishment actions are allowed. One example is extensions of time on the SOR, which has been ruled to not violate ex post facto even when the extension happens after the sentence has been given.
As I said, we can and we do. We just play creatively at it so we can pretend we don't violate ex post facto.