Assassin's Creed III: DESYNCHRONIZED Wrong weapon used

DESYNCHRONIZED: Wrong weapon used. Message alerting you of a Desynchronization in Assassin's Creed 3

If you use a weapon that does not match the mission objective (for example using a lethal weapon when mission calls for a non-lethal one), you will get Desynchronized along with the following message:

"DESYNCHRONIZED: Wrong weapon used."

Game will then revert to the last checkpoint