6, 2006, while trying to deliver a peace petition to the US Mission to the United Nations for International Women's Day. The case was sent to the jury on Friday at 2:30 p.m., and the jury did not reach a verdict on Friday. Deliberations will continue on Monday, December 11.

It started as a tiny act of protest. Cindy Sheehan, the mother of a soldier killed in Iraq who had held a vigil near President Bush's ranch, and a group of women wanted to submit a petition to the United States Mission to the United Nations in Manhattan, demanding an end to the war.

But Ms. Sheehan and three other women were handcuffed, arrested and jailed overnight. Now their misdemeanor trial in Manhattan Criminal Court has turned into a look at the use - and they say abuse - of police power, in the face of an antiwar protest.

At the trial, the police and security officers told the jury that the four women had sat down and blocked the entrance to the building, and had resisted arrest by refusing to follow the instructions of arresting officers.

And yesterday, Peggy Kerry, the sister of Senator John Kerry of Massachusetts and a liaison at the mission, testified that she was planning to meet with the protesters, but told one of them that she would not meet with the press because that was not her job. After learning that they had a celebrity, Ms. Sheehan, with them, Ms. Kerry turned off her phone and had no further contact with them.

"I was angry that they had not told me Cindy Sheehan would be there," Ms. Kerry, a prosecution witness, said, under questioning by Ms. Sheehan's lawyer, Robert Gottlieb.

The women, who showed a television news videotape in court yesterday to buttress their case, say the police and the security staff at the building, a private office building run by the Macklowe organization, locked the doors, refused to accept their petition and hemmed them in from all sides.

The video shows police officers, some wearing helmets, moving in on the protesters, who are sitting in a public plaza. As the police handcuff the women leading the protest, the video shows Ms. Sheehan lying on the ground, hands behind her back, with her shirt pulled up and bra exposed.

An arresting officer testified that Ms. Sheehan asked him to pull her shirt down and that he did.

The police have testified that the arrests were routine. But the women say their treatment harks back to a pattern of excessive force by the police during the Republican National Convention in New York in 2004 and in other demonstrations around the city, a "policy of stifling dissent by arresting noted people," Mr. Gottlieb said yesterday.

He said that locking them up instead of giving them desk appearance tickets for misdemeanor offenses was "piling on."

Paul J. Browne, the deputy police commissioner for public information, said yesterday that the police "routinely accommodate dissent." However, he said, "individuals who choose to engage in civil disobedience and, I would maintain, expect to be arrested, often are."

On March 6, the day they were arrested, the four defendants - Ms. Sheehan, 49, who lives in Northern California; the Rev. Patricia Ackerman, 48, an Episcopal priest; Susan Benjamin, 54, known as Medea; and Melissa Beattie, 57, known as Missy, were participating in a series of events to celebrate International Women's Day. Mr. Gottlieb said they had no intention of being arrested and were scheduled to take a van to Washington that afternoon, a trip that they would miss.

The case is expected to go to the jury today. So far, none of the women have testified, and their lawyers did not say whether they would. The oldest of Ms. Sheehan's four children, Casey, a soldier, was killed in Iraq in April 2004 at the age of 24, and she has spoken out against the war ever since, most notably by camping out near President Bush's ranch in Texas in the summer of 2005.

A prosecution witness, Detective Frank Bogucki, said that as soon as the women appeared at the building on East 45th Street, senior police officers tried to steer them into a "designated area set aside for them opposite the U.S. Mission" while building security locked the doors.

Ms. Kerry said that she had originally agreed to meet with Ms. Ackerman and a delegation of Iraqi women to accept the petition. But Ms. Kerry said that when she saw Ms. Ackerman with a large group of protesters and members of the news media, she turned off her cellphone.

Richard Grenell, the mission's head of external relations and Ms. Kerry's boss, characterized the demonstration during testimony yesterday as a "media event." He said he had seen women dressed in pink, to signify their membership in Code Pink, an antiwar group, being followed by reporters, and had agreed to meet with two women in his offices, but not "in front of cameras."

Then building security officials intervened, he said, and decided to close the building to maintain public safety.

"These women in pink looked dangerous?" Mr. Gottlieb asked.

"It sounds like women in pink are innocent," Mr. Grenell replied. "But I was nervous that day. First of all, they were marching towards the mission. The police were coming. They clearly were happy, and they were not paying attention to anything else."