Rocah said the ACLU will have to see how the MTA follows up before it can consider the matter resolved. "Statements of policy don't mean anything unless officers and employees know what the policy is and follow it," he said.

Wells said the policy allowing photography had been restated to officers in February and March. He said the ACLU letter and a Baltimore Sun article Wednesday about the controversy would be brought up at roll calls throughout the week.

Wells said MTA officers may approach a photographer and ask to see identification as part of a "field interview." But he said compliance with such a request is voluntary on the photographer's part.

The MTA administrator said officers who are found to have misstated Maryland law or MTA policy in exchanges with photographers could be subject to disciplinary action.

"The chief is very aggressive with taking administrative action with employees who are not in line with our procedures and rules and regulations," Wells said.

The MTA is the latest of many transportation agencies across the country to be forced to back away from formal or informal curbs on photography in the aftermath of the terrorist attacks of Sept. 11, 2001.

Photographers and the organizations they represent report that police have frequently asserted expanded powers to forbid pictures and video of public infrastructure since the attacks. In some cases, such as the one Fussell documented on video in March, photographers have been detained.

One local professional photographer contacted The Sun to say that such actions are nothing new. Jack Eisenberg of Mount Washington said he was carrying his camera and walking to Lake Roland on a path near the light rail tracks in 2004 when two MTA police officers approached and said he was forbidden to take pictures.

Eisenberg said the officers demanded his film and threatened to seize his cameras before requiring him to walk with them back to the Falls Road station. The photographer, who has done freelance work for The Sun, said he was detained for about an hour and a half before a lieutenant came to the station and ordered his release.

Mickey Osterreicher, general counsel for the National Press Photographers Association, said Eisenberg's account of threats, detention and demands for film has been commonplace over the past decade. He said the MTA's response to the ACLU's threatened lawsuit was typical for an agency faced with the prospect of monetary damages.

"Why would anybody want to put themselves in harm's way and be liable for this kind of policy when they're basically trying to enforce a law that doesn't exist?" he said.

Meanwhile, the Maryland Department of Transportation expressed approval of the MTA administrator's position and said it would make sure its other agencies are aware of its policies permitting photography.

Department of Transportation spokesman Jack Cahalan said certain exceptions apply to secure areas of the port of Baltimore's terminals and to the tarmac at Baltimore-Washington International Thurgood Marshall Airport. But generally, he said, members of the public can take photos from any spot where they are legally permitted to be.

"Anyone can take whatever shots they want," he said. Cahalan said Maryland Transportation Secretary Beverley K. Swaim-Staley fully supports Wells' stance.

Cahalan said the department will make sure that employees of all of its agencies are informed of its policies permitting photography.

"It's one of those things you can't repeat often enough," Cahalan said. "You have changeovers in personnel, and clearly it's an issue that's worth restating."

In addition to the MTA, the department oversees the Maryland Port Administration, the Maryland Aviation Administration, the Maryland Transportation Authority, the Motor Vehicle Administration and the State Highway Administration.

Rocah described the department's response as "wonderful."

Osterreicher said it is important that agencies continuously educate employees about the right to take photographs because new recruits might think officials can forbid pictures in public places.

"Unless they're told otherwise, they may have that erroneous impression," he said. "At least for a while, I expect this to be just an ongoing battle to understand that photography is not illegal."