BOSTON - James "Whitey" Bulger's girlfriend, who is accused of helping the reputed former crime boss elude authorities during 16 years on the run together, will not co-operate with law enforcement authorities in their case against him, her lawyer said Thursday.

Catherine Greig's lawyer, Kevin Reddington, made the remark after Greig pleaded not guilty in federal court to a charge of conspiracy to harbour and conceal a fugitive.

Prosecutors say Greig actively helped Bulger escape capture, but her attorney says she was in love with Bulger and wasn't aware of the extent of Bulger's alleged crimes when she fled with him in 1995. Bulger is accused of participating in 19 murders while heading up Boston's notorious Winter Hill Gang.

The couple was apprehended in Santa Monica, California, in June, more than 16 years after Bulger fled.

When asked by reporters whether Greig would co-operate with authorities against Bulger, Redding said, "Not while I'm representing her."

"She's going to trial on the case -- that's it," he said.

Greig entered her not guilty plea during a brief appearance in U.S. federal court. The charge carries a maximum prison sentence of five years.

Greig has been jailed since she and Bulger were captured. She agreed to be voluntarily detained while her attorneys gather information to support her request to be released on bail, including real estate appraisals for two properties Greig plans to use as collateral -- her house and her twin sister's house.

During her arraignment, Reddington told U.S. Magistrate Judge Jennifer Boal that he is still working on documents to support her bail request.

"I think she's an excellent bail candidate," Reddington told reporters after the hearing.

When asked what's changed since Greig fled with Bulger 16 years ago, Reddington said Greig wants to be with her sister and move on with her life.

"Where's she going to go? Where's the incentive to take off?" Reddington said.

Greig smiled at her sister, Margaret McCusker, seated in the front row of the courtroom, as she was led in and again as she left.

She is due back in court for a status conference on Sept. 29.