Not exactly on point, but the 13th amendment doesn't actually outlaw all forced labor- the government can (and does) use forced convict labor for a whole variety of things. Edit: Obviously current discussion of it now breaks the 20 - year rule, but there are some great past threads on this line of history.

https://www.reddit.com/r/askhistorians/comments/bowcw9/_/enmgi4z This is a great answer about the use of chain gang labor by u/Georgy_K_Zhukov (also sorry bad formatting; I'm on mobile.)

The thread below has some great answers context on the 13th amendment not banning all forced labor, including some stuff on convict labor. It's worth a read while you wait for a good answer.

https://www.reddit.com/r/askhistorians/comments/48o0zj

u/sowser gave some great answers.