An attorney for the Prince George's County woman accused of slaying her husband, an off-duty police officer, said yesterday that she was acting in self-defense.

Cpl. Thomas R. Smith, 31, was shot and killed about 12:30 a.m. Sunday at his Lanham Lane home in Camp Springs. His wife, Cynthia Lynn Smith, 25, was arrested and charged with first-degree murder, and released yesterday on a $5,000 bond.

At the bond hearing, Cynthia Smith's attorney, Courtland Townsend, said she became angry when she learned that her husband was at a Waldorf, Md., bar dancing with another woman.

Townsend said Cynthia Smith drove to the bar, where she confronted her husband and the couple engaged in a heated argument with a lot of "shouting and screaming."

Assistant State's Attorney Laura Gwinn said that at one point during the argument, Thomas Smith threatened his wife.

The couple left the club together and continued fighting on the way home, according to Townsend. Once in their house, Cynthia Smith told her husband to "leave her alone," Townsend said.

Townsend said she got his gun from their bedroom and went into their son's nursery. Townsend said Cynthia Smith told her husband not to enter the nursery, and when he did, she fired once.

The bullet was fired at close range and struck Smith between the eyes, according to Gwinn. He was pronounced dead at the scene. The six-year member of the force was assigned to the Oxon Hill District in southern Prince George's County.

After shooting her husband, Cynthia Smith called the police and, with the help of a dispatcher, tried to give her husband cardiopulmonary resuscitation, Townsend said.

The argument had been one of many the couple had been having recently, according to Townsend. "The relationship had been strained," he said of the 18-month marriage. The couple's son is in the care of Cynthia Smith's mother.