A minute after I took this picture, an officer of the Maryland Transit Police stopped me. He told me that I was not allowed to take photos of the trains. He called for backup. They arrived a few minutes later, blocking the tracks with their cruiser: 3 uniformed, armed men to deal with one photographer. They questioned me. They called headquarters and ran my driver’s license.

One officer told me that because of 9/11, I needed to be careful. I mentioned the Constitution. He said that the First Amendment “did not apply” in a time of war.

It’s natural for police to be careful. I appreciate that. I’ve had officers in Houston, San Francisco, New Jersey, and San Francisco greet me politely, ask me what I was doing, and wish me a good afternoon.

But we all have a right to take photos. Photos are a means of documentation, and documentation is fundamental to a free society. Photos show injustice, prove wrongdoing, and record history. Throughout World War Two, hobbyists continued photographing trains. The result is a lasting chronicle of the hard work American men and women put into the war effort. I won’t pretend any of my transit photos are that significant. But my photos do document what public agencies do with public money in public places. I paid for part of the Baltimore light rail system; I have a right to know what it looks like.

The Constitution was on my side, not the officer’s. Common sense was on my side, too. If someone has the skills to make a bomb and the messed up mind to want to set it off, they don’t need a photo to blow up a train. They just need to know where the nearest station is. If I did want to attack, would I be calling attention to myself by wandering around in the open, blatantly showing a camera?

METRO is deploying extra security for the Fourth of July. I’m glad they’ll be there. But it’s important that (unlike the cops in Baltimore, or the transit police in Atlanta who held me on top of a parking garage and told me I could call my wife but not tell her where I was, or the security guard in San Diego who said I could not take photos while the train was in a tunnel, or even the train operator in Newark who said the click of my shutter was a safety hazard) they remember that they are here to protect our freedoms, not ignore them.

Have a happy Independence Day.

More on photography rights:

• Bert Krages II photographers’ rights page
• NYCSubway.org on the successful effort to stop a photography ban in the New York Subway
• transit photo policies nationwide
• Free Our Streets (thanks to Live From the Third Rail)