A Viewer Writes: Bait then grab?

Joe- have you ever heard of the SPD doing anything like this before. This morning I was at a shopping center here in Salisbury when I walked outside to wait for my husband I noticed a SPD car parked in front of the door of the store I walked out of. He had 2 men in the car with him but they were in plain clothes looked like ones he would have apprehended or good disguise. He handed the one in the backseat something and motioned for him to do something the guy got out and positioned a cell phone in front of the store leaning against like the door frame and then he went back to the police car. About 30 min later the officer got out of the car picked up the cell phone and put it in front of one of the pillars in front of the store and after seeing me watch him got back into the patrol car. About another 15 min later he picked up the cell phone and rode off. Is this some kind of thing they are trying to do to see if someone sees the cell phone and steals it then arrest them? Seems like kind of a set up is this even legal? I swear it happened., and I was not the only one that saw it.