At first I said to myself "he didn't do it, he isn't a cop..." and then I started to think about the source of the information.
I'm not taking sides here. I don't know if he did it or not. I just like to question all sources at this point. Just because they say they didn't do it, doesn't mean they didn't do it.
I'm saying that cops telling you he didn't do it, seems like a questionable source to base your opinion on.
That they denied it is just additional (weak, sure) evidence.