In addition, behavior-recognition teams will be dispatched throughout the subway and bus system as part of the program. Those officers will be authorized to search a person’s bag if they believe it is warranted.

I don't buy the arguement that this is constitutional. It doesn't fit the parameters of the NYC system. Specifically "behavioral teams" are looking for anyone who might be nervous. This is targeted, not random, and doesn't rise to probable cause.

Police to Start Inspecting Bags on Boston Subway