Sending bad data won't prevent anything either, It will merely slow down the peers by wasting bandwidth. Torrents by nature work against bad data being receive

Sending bad data won't prevent anything either, It will merely slow down the peers by wasting bandwidth. Torrents by nature work against bad data being received by hash checking each chunk of data. (You can't trust anyone on the internet). Most clients would simply block each "bad" peer after several bad chunks.