Accused spy Benjamin Bishop has a dangerous mind.

At least that’s the argument the federal government is making to keep the Honolulu defense contractor locked up while he awaits trial on espionage charges.

Bishop, 59, was arrested March 15 for allegedly telling his 27-year-old Chinese girlfriend top secret details about the U.S.’s nuclear capabilities and defense protocols.

Bishop worked at U.S. Pacific Command (USPACOM) under a defense contract, and was a lieutenant colonel in the Army Reserve.

On Thursday, he was in court to argue he should be released from the Federal Detention Center in Honolulu, where he is being held without bail.

Federal Magistrate Judge Richard L. Puglisi had already ruled on March 25 that Bishop’s knowledge was enough of a threat to national security to keep him under constant lock and key.

But Bishop’s attorney Birney Bervar appealed that decision to U.S. District Court Judge Leslie E. Kobayashi, who heard arguments Thursday for what should happen to the accused spy.

The U.S. Attorney’s Office wants Bishop to remain in federal custody because he’s believed to be a flight risk and a danger to national security.

Specifically, the federal government is worried that if Bishop is not constantly monitored he’ll find a way to skip town or communicate with his girlfriend. Even though he doesn’t have access to classified information anymore, prosecutors say in court records his memory of those top secret details is enough to make him a national security threat.

“The best way to maintain him, to keep him from endangering the community, is to keep him at the Federal Detention Center,” Assistant U.S. Attorney Kenneth Sorenson said during Thursday’s proceeding. “It is the only hope of keeping him from having contact with Person 1.”

“Person 1” is Bishop’s mysterious Chinese girlfriend, who was living in the U.S. with a visa. According to court records, Bishop met Person 1 during an international military defense conference in Hawaii. That meeting then blossomed into a romantic relationship.

Officials won’t say whether Person 1 is still in the U.S., or whether she’ll be arrested. They only say that the matter is still under investigation. During Thursday’s proceedings, however, Sorenson made the People’s Republic of China citizen sound menacing enough to warrant an international manhunt.

“All (Bishop) has to do is dial a number and he’s back to his Chinese girlfriend talking about things,” Sorenson said.

Sorenson noted that Bishop has extensive foreign travel experience, and that since April 2011 he has left the country six times, twice to meet with his Chinese lover in Europe.

Bishop also lied to federal authorities on three occasions, Sorenson said. Bishop allegedly told officials he didn’t have guns or classified houses in his house when in fact he did.

The defense contractor also initially mischaracterized his relationship with the Chinese woman he’s accused of funneling nuclear information to, Sorenson said.

But Bishop’s attorney, Birney Bervar, calls the federal government’s assertions about his client overblown. Not only does Bishop have strong ties to the U.S., Bervar said, but he was a trusted government official for several decades has he rose to the rank of lieutenant colonel.

“You don’t rise through the ranks like that unless you’re a trusted and reliable person,” Bervar said. “He’s a very trusted individual, one they relied upon to be most important to this country’s affairs.”

He added that Bervar would have to have “excellent character” to get the sort of security clearance he had, which usually involves extensive vetting of family and friends.

Kobayashi is expected to make a decision next week on Bishop’s fate. She said during Thursday’s proceeding that she was looking at possibilities of placing him in the Mahoney Hale with certain restrictions on who he can talk to and what electronic devices he’s allowed to use, such as cell phones or computers.

But like Puglisi, Kobayashi expressed her concern about the classified information trapped in Bishop’s brain.

Her worry stemmed from confidential documents the federal government shared with her about his work. This information was not made available to Bervar, and was reviewed by Puglisi and Kobayashi behind closed doors.

“If we’re talking about dangers to the community,” Kobayashi said, “we’re talking about communication.”