One of the things the article doesn't point out (but the linked case law does) that I was curious enough about to look into:
The "beeper" was essentially a short-ranged RF transponder used as a tracking device. The officers were actively following the suspect, and using it as an aid to tailing the suspect's car. The suspect lost the tail, and the cops used the beeper to find where he went.
This is contrasted with a GPS device, which was placed, tracked for a month, and then retreived, and the data of the month's movements used to convict the drug dealer.
The "beeper" was essentially a short-ranged RF transponder used as a tracking device. The officers were actively following the suspect, and using it as an aid to tailing the suspect's car. The suspect lost the tail, and the cops used the beeper to find where he went.
This is contrasted with a GPS device, which was placed, tracked for a month, and then retreived, and the data of the month's movements used to convict the drug dealer.