NEW : DeSalvos ` ` outraged , and ` ` by secret DNA collection , their attorney says . So Boston Police Commissioner Ed Davis said he had a detective from the police department 's fugitive squad shadow DeSalvo relatives until he spotted one of the suspect 's nephews throwing away a water bottle . ME : ` ` We have offered them DNA as recently as last year , '' the attorney says . DNA from a relative links Albert ##son to the last Strangler victim , Mary Sullivan . DeSalvo was never charged in the murder and was sentenced to death in 1973 .
NEW : DeSalvos ` ` outraged , and ` ` by secret DNA collection , their attorney says . ME : ` ` We have offered them DNA as recently as last year , '' the attorney says . DNA from a relative links Albert ##son to the last Strangler victim , Mary Sullivan . DeSalvo was never charged in the murder and was sentenced to death in 1973 .