Since the beta version of Love some AIs are equipped with Teleporter Guns. Getting hit by a Teleporter Gun will teleport you to a jail point, you will be removed you from your settlement (if you've been a member of one) and if you had a Checkpoint it will be removed, too.
The jail itself is supposed to be an enclosed room in an AI base. A part of the wall is editable so players can free themselves from jail.
Also your actual respawn point will be set to the jail's location so you can't instantly respawn to your base or checkpoint.