I think both belief systems are credited with a lot of bad things. Stalin, Mao, and Hitler all used Atheism to perpetrate their atrocities, for example. But when it comes right down to it, it has nothing to do with deism or atheism at all. These are all just people trying to get what they want in ways that they would themselves consider wrong if they weren't blinded by desire. Religion, patriotism, ethnicity, etc. are all used as excuses, not reasons.
Amonk is right, Atheism isn't exactly picture perfect. Secondly the idea that catholic priest are molesting children because they're catholic is inherently stupid, I think pedophiles molest children; there is nothing about catholocism that says to molest children like a terrorist flying into a building would say there was for his act of matyrdom.