can i get banned for joking

LiannaSilverwind: You can be reported for intentionally shooting friendly targets, be deemed guilty of intention of causing damage to friendly vehicles and banned. I would not advice doing so.
It also stresses your team, because your teammates may view you as potential team-killer, watch their backs and not focus enough on the enemy.
It's similar to "I poke my friend's back with my dull knife, he agrees with that, why do policemen react strangely?"