If they "cut him a sweet deal", then he's working for the State.
No, as long as the state had no prior knowledge that he was going to enter the apartment, he's not the state's agent. Criminals provide evidence against other criminals all the time. They don't have to have known each other.
Ah yes, but...........how in God's name would a judge know if the cops had prior knowledge? Should the judge simply take the state's (cop's) word for it? Cutting the burglar a "sweet deal" is evidence enough that "something stinks in Omaha". In any event, if a judge simply allows the evidence without asking the cops and prosecuters some really tough questions, it won't be long before cops recruit an army of "burglars with scruples" to circumvent that whole "search warrant fourth ammendment thingy". The best way for the judge to make sure that there is no monkey bussiness going on is to require that the burglar be prosecuted to the fullest extent of the law, or dismiss all evidence collected because of the burglary. Heh, the burglar broke the law, too. Breaking and entering is a FELONY.
Be honest. How would you like the cops to send an army of burglars (who have been given immunity from prosecution) to break into your house, because the cops have a hunch that you may own a gun, have politically incorrect literature, etc.? How would you like the cops to send a "burglar" to break into your home, plant drugs, "find" those drugs, report the "findings" to the cops, have you arrested, seize your home under confiscation laws for drug trafficing, then you get to watch their hero (the "burglar") collect his cash reward and walk free to break into another home, while you lose everything including your freedom? In the meantime, the cops get to keep your property. All this, because a so-called burglar "found religion while breaking into your house and simply had to tell the cops about you." Yeah, right. Sure he did. That may sound cynical, but that exact crap has been going on for years. Read "LOST RIGHTS" (I forget the author's name).
"Law and Order" Republicans had better be careful what they wish for. One day the "criminal" getting his ass kicked may be that same law abiding, but naive Republican.
A few final thoughts: it is believed that Anne Frank's family was turned in to the Gestapo by a burglar who got caught and was out to save his own ass. Kinda gives me the creeps about burglars talking to cops about the interesting things they've encountered while violating the rights of others. Yes, the kiddie porn creep should be prosecuted, but so should the burglar. Anything less is an injustice.