i'm putting my vote down for a day or two ban, due to repeated offenses, and the fact that this is clearly spellled out in the rules:

Sabotage – Killing other players by in game map tricks, bugs, and purposeful tagging
  • Using map triggers to kill team mates (IE Blowing up the bridge)
  • On escape maps, shooting map made barricades that were designed to hold zombies (IE Doors on Mines of Moria)
  • Sitting in a spot to purposefully get tagged and kill the rest of your barricading group.