Boston — The longtime girlfriend of Boston gangster James "Whitey" Bulger was sentenced Thursday to an additional 21 months in prison for refusing to testify before a grand jury investigating whether other people helped Bulger while he was a fugitive.

Catherine Greig already is serving an eight-year sentence for helping Bulger while he was a fugitive.

Greig spent 16 years on the run with him before they were captured in Santa Monica, Calif., in 2011.

Federal prosecutors had asked the judge to add a little more than three years to her prison time for her conviction on a criminal contempt charge.

Greig's lawyer asked for leniency and said she should not get any more than six months.

"It is obvious that she is a kind, gentle woman who has literally done nothing bad in her life except fall in love with James Bulger and live with him for 16 years until their arrest," he wrote in a sentencing memo.

Prosecutors said Greig refused to answer questions before the grand jury even after she was given immunity and after a judge issued an order compelling her to testify.

They argued in a sentencing memo that she should be sentenced to a little more than three years "for her conscious, considered, and unapologetic violation of the law."

Greig already had nine months added to her prison time after she was found in civil contempt for refusing to testify before the grand jury.

Bulger, now 86, is serving a life sentence after being convicted in 2013 for playing a role in 11 murders.

He has denied involvement in the crimes.