Back during Henry Lee Lucas, they closed a boatload of cases. Never mind he didn't do many of them but it got them off the books.
Interestingly enough, the one crime that condemned Lucas to death, the murder of a still-unidentified Jane Doe known as "Orange Socks" was one that later investigations showed Lucas was unlikely to have committed, resulting in then governor George W. Bush commuting Lucas' sentence to life in prison. He died in prison not long thereafter.