No, the concern with slavery is the lack of agency for oneself at the behest of another. A slave has no say in how their body is used and it’s a violation of the human rights to be your own person. Whether or not they are guilty of a crime is irrelevant.

Punishment for a crime does not mean permitting abuse. It means rehabilitation or isolation from others. They can still be their own person and aren’t forced into labor, but are not allowed to be a part of society again.