Is it excusable to steal from a thief?

Question

Let's say you sneak into a robber's house and you see a nice shiny new crowbar laying by the door. Is it legally okay to take it, knowing full well that they're going to use it later that night on some innocent neighbors?

Answer 1

your breaking the law as much as they are planing on.  

Answer 2

Theft is theft.

Who appointed you judge and jury?  You do not KNOW that it will be used as you say, you THINK it will.

Theft is theft, stealing is wrong.  

Theft is also illegal, under ANY circumstances.

Answer 3

don't be a thief for vengeance.