Legitimate implies legal, and legal it is not. It's a fine line between bending the rules an breaking the rules and any lawyer worth their salt will get their client off the hook if the police are found to be bending the rules.

If there is one thing more dangerous than criminals then it is authorities operating without any checks on their power.

So if you want criminals to be punished for their deeds you should be very much against police bending the rules to catch them.

Ideally they would capture a rapist without breaking the law.

> That doesn't help the victim.

The point of putting people in prison isn't supposed to be to help the victim, either. The victim is kind of irrelevant.