In America, there is a big problem. When a serious crime like murder happens, the police come to help. They look for the person who did it. Their job is to find answers for the victim's family.
But sometimes, the police cannot find the killer. They look for clues and talk to people, but they find nothing. The case stays open. This means the bad person is still free.
When killers are not caught, families feel very sad and scared. It is not fair. It also makes communities feel unsafe. Everyone wants the police to solve these important cases.