I've only had trouble finding the correct suspect one time. The clues pointed to a female blonde geek sim wearing a short skirt. I sent out several APBs but there was never a sim matching this description at the locations.
I eventually noticed that there was always this one sim that was present even though they did not match the description (she didn't have blonde hair and she was in the princess leia outfit). I did the "get to know" interaction with her and found out she was a geek so I arrested her and turned out to be correct.
This is what I think happened. Due to the fact that random townies love to pick the most hideous outfits for themselves, when I'm playing I do have a tendency to take them into CAS and edit their look. I'm guessing I had done this with this townie but the game never registered the change in appearance and the game still thought she was wearing her old clothes and hair.
So FYI if you are serial townie makeoverer like me it could cause you to have issues identifying the correct sims.
