One member of the group monitored a police car parked on the waterfront by using binoculars as well as listening to police-radio transmissions.
The landscape rolled by unseen; a friend from the other end of town spoke to her on her cellphone, relaying news from someone who was monitoring a police scanner.
Mr. Braun, former Drug Enforcement Agency chief of operations, recalled helping to monitor a group of police officers pursuing a drug plane in southern Mexico in the early 1990s.
The police can monitor a fire hose of social media posts to look for evidence of criminal activities; transportation agencies can track commuters' toll payments when drivers use an electronic pass; and the National Security Agency, as news reports this summer revealed, scooped up telephone records of millions of cellphone customers in the United States.
Jones, the justices ruled that, when officers attach a GPS tracking device to a car to monitor a suspect's movements, the police are indeed conducting a "search" under the Fourth Amendment.
A G4S custody officer has resigned after a man he was monitoring in a police cell was found collapsed.
"No federal judge has ever imposed a monitor over a police department after a civil lawsuit," Bloomberg said Monday.
A computerized system to monitor state police activity, a key to reforms intended to end racial profiling, should be fully in place within six months, the attorney general has said.
Earlier on Saturday, at 4 30 a.m. in Prospect Heights, Brooklyn, a uniformed officer was monitoring a van that the police believed held a gun used in a shooting earlier on Saturday, waiting for a search warrant.
Miami-Dade Police were monitoring a suspected gambling operation in Liberty City when they noticed a rotating shift of six off-duty City of Miami police officers protecting the storefront, reports the Miami Herald.
