Quote of note:

At the core of all three cases are questions about the expanded powers the police were granted after the 2001 attacks, and how much the department needs to know about the politics of people who are expressing their views.

In 2003, a federal judge eased longstanding and strict limits on surveillance of political activity at the request of lawyers from the city's corporation counsel office, who argued that the Police Department needed broader authority to use such tactics to fight terrorism.

Since then, police officers in disguise have taken part in demonstrations, an approach the Police Department says it used before receiving the expanded powers; other officers have made hundreds of hours of videotapes of people involved in protests and rallies, very few of whom were charged with breaking any law. Neither form of surveillance, the city argues, violates the Constitution.

Surveillance Prompts a Suit: Police v. Police
By JIM DWYER

The demonstrators arrived angry, departed furious. The police had herded them into pens. Stopped them from handing out fliers. Threatened them with arrest for standing on public sidewalks. Made notes on which politicians they cheered and which ones they razzed.

Meanwhile, officers from a special unit videotaped their faces, evoking for one demonstrator the unblinking eye of George Orwell's "1984."

"That's Big Brother watching you," the demonstrator, Walter Liddy, said in a deposition.

Mr. Liddy's complaint about police tactics, while hardly novel from a big-city protester, stands out because of his job: He is a New York City police officer. The rallies he attended were organized in the summer of 2004 by his union, the Patrolmen's Benevolent Association, to protest the pace of contract talks with the city.

Now the officers, through their union, are suing the city, charging that the police procedures at their demonstrations — many of them routinely used at war protests, antipoverty marches and mass bike rides — were so heavy-handed and intimidating that their First Amendment rights were violated.