(The opinions expressed below are mine alone. I do not speak for the railroad or other railroad employees.)
Recently, WTNH reporter Alan Cohn filed an investigative report in which he left his briefcase on a Metro North train. The purpose of this excercise was to see if anybody would notice an unattended bag, and if they did would they report it (see link):
As you can see in this video, nobody noticed the briefcase. It has been my experience, however, that people do notice, and they do say something.
I am regularly summoned by concerned passengers who have spotted unattended bags/packages. The conversation usually starts with ... "Conductor, I may be paranoid, but..." I assure the passenger that they're right to be concerned and then I check the bag out. Ninety nine percent of the time, the bag owner is in the lavatory, or moved seats to talk to a friend. After finding the bag owner, I usually lecture him/her about leaving their bags unattended. "We live in different times," I tell them.
If nobody does claim a bag, things get a little dicey. If we had to call the police everytime we found an unattended bag, we'd be delaying a lot of trains. So, the rules of thumb are:
Does the bag look suspicious?
Are there exposed wires?
Are there batteries attached?
Is the bag/package wrapped in duct tape?
Is there an oily surface?
Was someone seen putting the bag on the train and then leaving quickly?
Did this person look nervous or agitated?
If the answer to any of these questions is "yes" we call the MTA police.
Occasionally the railroad police set up a card table in Grand Central and inspect commuter's bags. In my opinion this is a big waste of time. They check one person out of a million, and because of profiling concerns, they have to check a cross section of commuters, whether they look suspicious or not.
I agree with James Cameron, The Commuter Council President. Cameras on trains will only be useful after the fact. Better trained officers and train crews (we are given some training) should be the first line of defense. Besides, history has shown, suicide bombers don't leave their packages unattended.