In 1994, Larry Seay took the D.C. police oath to protect and serve the residents of the District.

Years later, prosecutors say, Seay abandoned that oath and sexually assaulted three women while he was in uniform patrolling his Northwest Washington beat.

Seay, 39, a 3rd District patrol officer who has been suspended without pay, is charged with several counts of sexual assault. The women at one time worked as prostitutes in the area of 11th Street and Massachusetts Avenue NW, where Seay patrolled, prosecutors said.

During a trial that started this week in D.C. Superior Court, Seay’s attorneys, Renee Raymond and David Knight of the District’s Public Defender Service, said that their client is innocent of the charges and that any sexual contact was consensual.

One of the women, a 32-year-old resident of Southeast Washington who went by the name “Snowflake,” testified Wednesday that she was accosted one evening in July 2010 as she walked to a gas station to buy a pack of cigarettes. She said she was seven months pregnant at the time.

The woman said Seay approached her, asked where she was going and searched her purse. She said he ordered her to meet him in an alley, where he offered her $50. Seay told her that if she refused him, he would “make something happen” and arrest her, the woman testified.

The woman testified that she and Seay went into an apartment building and that he assaulted her in the stairwell. “I was scared and very reluctant,” the woman testified, at times her speech slurred and eyes droopy.

During cross-examination, Raymond asked the woman if she was on any narcotics, and the woman said she was using methadone because of a heroin addiction. Raymond repeatedly brought up numerous drug and solicitation cases against the woman, including several that had been dismissed. The Washington Post generally does not name alleged victims of sexual assault.

A second woman, who is now a college student in Northern Virginia, testified that she had worked as a dancer at the Archibald’s Gentlemen’s Club and that she was walking to meet a friend in July 2010 when Seay, in a police van, stopped her and ordered her to meet him in a nearby alley.

The woman, who went by the name “Cakes,” admitted to being a drug user and said she had worked as a prostitute to support her habit.

The 38-year-old woman testified that Seay refused to wear a condom. “He made me have sex with him when I didn’t want to unprotected,” she said, at times in tears.

The woman said after they had sex, he threw $40 on the ground and wiped himself with a tissue. She said she stuffed the tissue and money in her purse and then went to a hospital, where she told a nurse she had been raped by a police officer.

The woman told the jury that she filed a $3 million civil suit against the city after she testified before the grand jury. Under cross-examination by Knight, the woman said she had not been employed by Archibald’s but had worked there as a “freelancer.”

Knight played a security videotape that shows Seay as he tries and fails to open the door to a building before walking away. The video then shows the woman standing alone for about five minutes before Seay returns. Knight asked the woman why she didn’t run away. She replied that she was afraid to try.

The trial is expected to continue Thursday before Judge Robert E. Morin.

This jury will consider only charges involving two of the three alleged victims. A separate trial has been scheduled regarding the third, authorities said.

The Seay case is not the only recent criminal case involving a D.C. officer.

In October, an officer was charged with firing his service weapon into an occupied car after trying to pay a transgender woman for sex in 2011. The officer, Kenneth Furr, was acquitted of the more serious charge of assault with intent to kill but was found guilty of solicitation and assault with a deadly weapon.

In another case, Wendel Palmer, a 22-year veteran of the force, is awaiting trial on charges that he sexually assaulted a teenage girl.