I still find it abhorrent that incarcerated people can't vote in the US. That seems so obviously exploitable.
Most people in jail retain the right to vote, regardless of state.
People currently in prison on felony charges CANNOT vote in most states, but this is up to each state. In many states, you get your enfranchisement restored after completing your sentence.
https://www.thoughtco.com/where-felons-can-and-cannot-vote-3...
They may have the right to vote. Whether the facility lets it actually happen is another matter.
Edit: I stand corrected, this is true in some states but not others.
https://www.aclu.org/issues/voting-rights/voter-restoration/...
There are just a couple of states that allow that, but I learned that quite a few jurisdictions restore rights after incarceration, after probation, etc...
Not the opposite!