DeSalvo was incarcerated in what is now known as MCI-Cedar Junction prison in Massachusetts. In November 1973 he got word to his doctor that he needed to see him urgently. DeSalvo had something important to say about the Boston Strangler murders. The night before they were to meet DeSalvo was stabbed to death in prison.
Because of the level of security in the prison it is assumed that the killing had been planned with a degree of co-operation between employees and prisoners. Whatever the case, and although there were no more murders by the ‘Strangler’ after DeSalvo had been arrested, the Strangler case was never closed.
In 2001, DeSalvo’s body was exhumed and DNA tests were taken and compared to evidence taken from the last Strangler victim, Mary Sullivan. There was no match. Although this only proved that DeSalvo had not sexually assaulted Ms Sullivan it didn’t rule out his involvement in her murder.
The family of DeSalvo and the nephew of Mary Sullivan continue to believe in Albert DeSalvo’s innocence of the murders of thirteen women. They are convinced that the killer is still alive.  Despite calls from both families for evidence to be brought forward so they can reactivate lawsuits, the state of Massachusetts has so far declined.