Baltimore police officers were ordered to remove their badges and nameplates before going into the infield of the Pimlico Race Course during the Preakness last month, police said.
The removal of badges and names was apparent on a videotape released yesterday by city prosecutors that shows an officer hitting a spectator with an object that appears to be a baton.
The absence of badges and nameplates was criticized by civil libertarians worried that officers might be trying to hide their identifies, and the department's top lawyer said the practice was "a real concern" and could hurt police accountability.
However, police said the practice was the result of previous Preakness races when spectators ripped off badges and nameplates as souvenirs.
It is unclear how widespread the removal of badges and nameplates was during the Preakness on May 18, but several officers, who spoke on condition of anonymity, said they attended a roll call with about 100 others just before the event and a lieutenant ordered them to remove the items.
"It raises concern because when the police officer cannot be identified as readily, that may make the police officer engage in conduct that the officer wouldn't normally engage in," said Dwight Sullivan, a lawyer for the American Civil Liberties Union in Maryland.
Police spokeswoman Ragina C. Averella said internal affairs detectives were looking into the matter, though she could not confirm whether any order had been given.
Sean R. Malone, the department's chief legal adviser, said that "officers are supposed to be accountable to the public."
"Name tags and badges are part of that accountability process," Malone said. "By removing them, it runs counter to that goal. It's a real concern."
The videotape showing the officers without badges and nameplates was first aired Friday by WBAL-TV. It shows a melee in the infield involving at least 20 people. Spectators are punching and stomping each other; one man hurls a lawn chair, and beer cans can be seen flying through the air.
In the video, police officers can be seen trying to gain control of the crowd when an officer in a yellow jacket rushes into the fighting. The officer - identified by police as Troy Chesley, an eight-year veteran - then takes a swing at a spectator with an object that appears to be a nightstick, the tape shows.
