BOSTON (CBS/AP) — The girlfriend of reputed mobster James “Whitey” Bulger is expected to plead guilty this week to charges of harboring a fugitive, as part of a plea deal with the government.

On Monday, prosecutors told family members of Bulger’s alleged murder victims that Catherine Greig will plead guilty to two charges in California over shielding identities and one charge here in Massachusetts for harboring a fugitive.

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Under the agreement, Greig will not have to testify against Bulger. There will be no recommendations on sentencing, but the families say they were told that in exchange for her plea, Greig will not face any additional charges.

Tom Donahue, whose father was allegedly killed by Bulger in 1982, says prosecutors told him Greig will plead guilty Wednesday to the harboring charge as well as conspiracy and identity fraud charges.

“I’m not happy with the deal. I’m not happy with any deals. Everybody had gotten a sweetheart deal. I want to see somebody finally get charged to the full extent of the law,” he said.

Greig is accused of helping Bulger evade capture during their 16 years on the run.

Steven Davis, who says his sister Debbie was murdered by Bulger, is also upset with the plea. He says, “I feel the government is not putting a tight enough grasp on the whole situation. At one point they said they would be worried about a 12 man jury. I said I would take a shot at that in a minute.”

Davis’ brother Robbie says he understands the US Attorney’s office is keeping it’s focus on Bulger.

WBZ NewsRadio 1030’s Bernice Corpuz reports

Bulger is charged in connection with 19 killings. He and Greig were captured in June in Santa Monica, Calif.

Greig could face anywhere between three and fifteen years in prison.

The Donahue and Davis family say despite their frustration, they are glad the US Attorney brought them in to explain the proceedings. They believe US Attorney Carmen Ortiz will stand by her word to them, and not let Bulger off with any kind of plea deal. “She’s a fighter,” Steve Davis said of Ortiz.

WBZ-TV’s Karen Anderson contributed to this report.

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