Donna Hoffmann sat demurely yesterday in her blue dress and white sweater as witnesses testified that she was a woman who rarely spent nights with her husband and had smoked PCP cigaretts while helping to plot his murder.

Jeffrey Scott Whittaker, 19, who pleaded guilty in connection with the Dec. 15 killing of Michael Hoffmann, 20, testified in the third day of the trial that Donna Hoffmann had two concerns as she talked of the murder scheme: that her husband's body be safely hidden and that she would be quickly whisked away from the lonely Aquasco, Md., road where he was to be shot.

"The general subject of the discussion was the murder of Mr. Hoffmann," Whittaker said of a meeting he, Hoffmann, John Penkert, 26 -- Donna's boyfriend -- and Stephen Troese, 19, had at Troese's house only hours before Michael Hoffmann was shot. He testified that at that meeting the group smoked the synthetic drug PCP, the use of which has been linked with violent crimes.

"Mr. Troese was doing most of the talking and Mrs. Hoffmann was doing the second most talking," Whittaker testified. "She said, 'What are you going to do with the body and how are you going to get me out of there?'" Troese also pleaded guilty in connection with the killing.

Whittaker, who testified in return for a recommendation of a lighter sentence, contradicted Hoffmann's lawyer, Karl Feissner. He has argued that Hoffmann never participated in the murder plan.

The prosecution has maintained that Hoffmann not only helped plan the murder, but also drove her husband to the murder scene and paid the gunman, George Harvey, 23, $100 immediately after Hoffmann was shot in the head and chest.

Donna Hoffmann has been charged with first-degree murder and accessory after the murder in the death of her husband of three months. He was a civilian clerk at Andrews Air Force base. Donna Hoffmann led police to the scene of Hoffmann's murder. His body was found nearby in Black Swamp Creek in Aquasco the day after the murder.

She had made police suspicious about her husband's whereabouts when she phoned hours after the killing to report him missing. She later phoned police again to say she had found a note from her husband that said he had been kidnaped. She wrote the note herself, according to court testimony.

Two days after the murder, Hoffmann told police the names of all five young men who had participated in the murder -- all of whom pleaded guilty to charges of murder or conspiracy to commit murder. None has been sentenced.

Several witneses testified yesterday that Donna Hoffmann rarely spent nights at home with her husband. They said she spent much of her time with Penkert, before and after the murder.

Gregory Raymond Lynch, 19, of Oxon Hill, who lived with the Hoffmanns in their one-bedroom apartment for 1 1/2 months prior to the killing, said he saw Donna Hoffmann in her apartment only about a dozen times. Lynch said he had slept at the apartment every night and that she had slept there only three times.

When she was at home, Lynch said Donna and Michael Hoffmann would argue. "She'd get angry, start crying, start throwing things, throw plates, anything she could get her hands on," he said.

Donna Hoffmann had a different type of relationship with Penkert, Lynch said. When Michael Hoffmann was not home, Penkert sometimes would come to the apartment.

"They'd be holding hands, hugging, kissing," Lynch said. "She told me that she loved John Penkert, that he treated her better than Mike did."