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I was on the subway in Boston recently taking some pictures of my friends and I was told by a worker to stop. I didn't understand at all, because what I was doing was totally harmless- I wasn't taking pictures of anybody else around. I took a few pictures of the signs because some of them were old and I liked their designs. The subway is a public place, and I should have the right to take pictures just as if I was above ground walking through Boston.