"Whitey" Bulger Trial: Stephen Flemmi pins killing of his stepdaughter on former mob boss

(CBS/AP) BOSTON - Stephen "The Rifleman" Flemmi, the ex-associate of reputed gangster James "Whitey" Bulger, says Bulger killed Flemmi's stepdaughter because she was using drugs, getting arrested and dropping their names when she got in trouble.

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Flemmi, testifying Tuesday at Bulger's racketeering trial in Boston, says Bulger strangled Deborah Hussey because she had become uncontrollable.

During cross-examination, Flemmi denied a suggestion that he, not Bulger, killed Hussey.

But Flemmi also acknowledged that he twice had oral sex with Hussey in what he called a consensual act and "a moment of weakness."

Flemmi acknowledged that Hussey's mother had been his live-in girlfriend since Hussey was just a toddler and that she had called him "Daddy."

Bulger is accused of participating in 19 killings.

Flemmi pleaded guilty to 10 murders and is serving a life sentence.

Complete coverage of the Whitey Bulger case on Crimesider