Board Thread:General Discussion/@comment-32994909-20180507104612/@comment-32994909-20180507150038

That's true, but both a Bodyguard and Doctor can protect the Jailor. it says on the Bodyguard page
 * If you guard a Jailor,  Escort, Pirate or Consort who roleblocked a Serial Killer or Werewolf (on a full moon), you will save your target and kill the Serial Killer or Werewolf.

the Jailor is basically unkillable if it's protected by anything, on the first night anyway.