A lawyer representing gay former Army Lt. Dan Choi questioned five U.S. Park Police officers Monday over the validity of their decision to arrest Choi last November after he handcuffed himself to the White House fence to protest the “Don’t Ask, Don’t Tell” law.

Defense attorney Robert Feldman asked the questions while cross-examining the officers during the first day of Choi’s trial at U.S. District Court for the District of Columbia. Choi faces a possible sentence of six months in jail or a $5,000 fine if convicted on a misdemeanor charge of disobeying a lawful order to disengage from the fence.

Magistrate Judge John Facciola is presiding over the trial, which was expected to continue through Tuesday and possibly part of the day on Wednesday.

Choi and 12 other LGBT activists attracted national media attention on Nov. 15, 2010, when they handcuffed themselves to the White House fence. About 75 supporters who assembled across the street in Lafayette Park cheered and chanted slogans for LGBT equality while Park Police removed the handcuffs with cable cutters and placed Choi and the other protesters under arrest.

In May of this year, the 12 others who were arrested agreed to a government offer to plead guilty to the charge in exchange for the government dismissing the case against them in six months if the activists don’t get arrested during that period for any reason, including a similar civil disobedience protest.

Choi told reporters at a news conference outside the federal courthouse Monday, after the trial recessed for the day, that he rejected the government’s plea bargain offer because he believes the law and regulation used to arrest him is unconstitutional.

“I believe there is no law that, in the history of this country, abridges freedom of speech, assembly, or the right to protest for redress of grievances, which were clear and made plain by all of the defendants,” he said.

Assistant U.S. Attorney Angela George, the prosecutor in the case, called five Park Police officers and a U.S. Park Ranger as government witnesses on Monday. Under questioning from George, they testified that they had no intention of singling out the protesters for their political beliefs or because of their sexual orientation.

Feldman released an e-mail sent to the defense on Friday by George that extended another offer for Choi to plead guilty to the charge in exchange for the dismissal of the case by the government if Choi refrained from getting arrested for the next four months.

Feldman said Choi responded by saying he would accept the offer only on condition that the government issue a public apology to Choi in court on Monday for the arrest and prosecution against him. Feldman said the government rejected the conditions, prompting Choi to turn down the offer.

A spokesperson for the U.S. Attorney’s office said the office would have no comment on the case while the trial is in progress.

Park Police Lt. Robert Lachance, who led a team of officers assigned to arrest the protesters, testified that an assistant solicitor general at the Department of Interior, which has jurisdiction over the Park Police, advised him that the act of chaining oneself to the White House fence violated a federal regulation against actions that pose a threat to public safety, obstruct traffic, and potentially prevent “emergency responders” from carrying out their work.

At the news conference, Feldman said he plans to argue at the trial that Choi’s action at the White House fence did not violate the regulation and statute cited by the Park Police and by prosecutor George.

“It’s uncontroverted that Lt. Choi is no threat to the public safety whatsoever,” said Feldman. “Neither does he obstruct traffic, which is the second part of the regulation.”

Feldman said he would also argue that the regulation used by authorities to arrest Choi applies only to the sidewalk next to the White House fence. He noted that Choi and the other protesters were standing on a masonry ledge that rises above the sidewalk and serves as an anchor for the White House fence.

“It’s very clear that my client was never on the sidewalk,” Feldman said.  “He was on the masonry fence, which is above the sidewalk. And the warnings from Lt. Lachance said, ‘Get off the sidewalk.’ How can you get off the sidewalk if you were never on the sidewalk?”

He said he would also argue that Choi was unable to hear the warning that Lachance made to the protesters through a loudspeaker brought to the scene by Park Police. Lachance testified that he read a scripted message three times ordering the protesters to leave the fence and warning them they would be arrested if they did not comply with that order.

Feldman said Lachance’s warnings were drowned out by loud shouts and chants by Choi and the other 12 protesters handcuffed to the fence as well as by dozens of other protesters assembled in Lafayette Park.

The chants and shouts could be heard in a video recording of the protest that George played in the courtroom as part of a prosecution exhibit for the trial.

“There’s a cacophony of noise all around, and how can you possibly hear Lt. Lachance’s warnings to go away?” Feldman said at the news conference.

He said Choi would testify at the trial as the lead defense witness. One other defense witness, gay activist and former military Capt. Jim Pietrangelo II, was also scheduled to testify, Feldman said.