Sex crimes detectives say rapists are often the most difficult criminals to catch precisely because their crimes are so shocking that few people can imagine anyone they know committing them.
No one had ever suggested Sedrick Williams, charged with six of the rapes, as a suspect. He's in jail awaiting trial.
''People don't look at their neighbors or their friends like that,'' Sgt. Cecile Alvarez said. ``I think people don't want to think someone they know could be like that.''
The DNA discovery late last month was a lucky break for an investigation that was almost stalled. The rapes, which began Christmas Day 2002, stopped abruptly in late 2003 after a 7-year-old was attacked in front of her 8-year-old sister.
''I don't know him really. I just know he stayed in jail a lot,'' he said after learning Williams is the kid he used to know as Cory. ``But sure, when it's a part of the family, it's very shocking.''