A break-in occurred at a high school that involved the theft of several computers. At the time of the break-in, the building was empty. A motion detector in one of the hallways alerted police. When the police arrived, they found that one of the doors leading into the school had been propped open with paper wedged into the doorjamb. The door appeared to be locked, but it was not, and it could be pushed open. Near the door, police found a cold soft drink can. Because of the cool temperature of the drink, police suspected that the can was recently left by one of the intruders.
The can was bagged as evidence, and in the forensics laboratory, a DNA sample was obtained from the lip of the can. A clerk at a nearby convenience store remembered selling canned soft drinks to three young men just before the break-in occurred. The surveillance video in the convenience store was examined, and the clerk was able to provide the police with the names of all three young men who were in the store just prior to the break-in. The three young men were fingerprinted, and each provided a mouth swab containing their DNA sample.
