The Bible states very clearly, in several places, that it is not our place to judge.
Let he who is without sin cast the first stone. Remove the log from your own eye, that you may better see the mote that is in your neighbor's eye. God does not want us to judge, or to punish, sinners. He wants us to forgive them.
The one task Jesus gave his disciples was to preach the Gospel. If you want to tell people that they are headed for Hell, that's fine. But the mandate stops at words.