I have personally picked up a wallet and found the owner. What else are you supposed to do. Let it sit.
I'm not sure what the crime is. If a wallet is on the ground, does it have to sit there until a police officer picks it up? Is it illegal to pick up a wallet and see who may own it? I thought we were supposed to pick it up, if it was not obvious who it belongs, you take it to the police. If no-one claims it in a period of time, any cash would be yours.
I think it may be entrapment.
Wikipedia defines it (in short): jurisprudence, entrapment is a legal defense by which a defendant may argue that he or she should not be held criminally liable for actions which broke the law, because he/she was induced (or entrapped) by the police to commit said acts...
I don't think the cops have a leg to fall off of on that charge. They may have made the ARREST, but on what grounds? What law has been broken? None.
I've picked up a wallet, and collected the credit cards & such that were sprayed all over the onramp. Yeah, it was on an onramp to the Interstate. Took some digging through it before I finally found a name & phone number. The grateful owner brought me a bottle of wine as a reward.
I... uh... don't drink wine well. It SNAFUs up my sinuses something awful. So - I let 'em take it (the wine) home with 'em. What'd it cost me to get 'em back their wallet? A phone call? Fifteen minutes of my time? PFAUGH. Ain't no sense collecting a reward for THAT.
There's gotta me more to it than that. If a person picks up a wallet, he's broken no law and can not be arrested. If he/she proceeds to use the credit card in there, then there's cause. Like Sonny sez, the whole thing stinks to me. In NY, there's plenty of crime for the police to arrest people. No need to entrap any body.
I saw the same story, and the way it was presented, the guy sat on a bench in the subway, saw a wallet on the bench next to him. Since he had a meeting to get to, he put the wallet in his bag intending to later find the owner and return it. When he was about to board the train, an undercover officer tapped him on the shoulder and pulled him away to question him. He was not arrested since he did not open the wallet and remove the cash. If he had, he would have been arrested, and rightly so. If he had been arrested for what he did, I would agree that it would not be proper though not necessarily entrapment, but I don't think the police were out of line for doing what they did. The point of the police operation is to get people to immediately turn in found wallets to the nearest officer.
Years ago there was a ploy where an undercover cop dressed like a wino would pretend to be passed out in an alley or dark street with a $20 sticking part way out of his shirt pocket. Soo as someone lifted the bill the cop and his backup would come into action and arrest the culprit for Theft from a person, generally a higher offense than the value of the item stolen. That sort of thing bounced around in the courts for a long time. Don't know what the conclusion was but. . . that is quite different than merely scooping up a lost wallet, whether turning it in to the nearest cop or not. One would think that even the Transit Cops in NYC would have a more productive use of their time.
Is it entrapment? No, this is merely offering the person the opportunity to commit an offense, if not doing the right thing is an offense. Surely, if it is an offense to not immediately turn found property in to authorities, it must also be an offense to not help someone being mugged on the street, and that happens all the time with others just walking on by.