CARIBOU (AP) – Tim Hortons customers who apparently interrupted a fatal attack testified Tuesday about being served by an angry and distracted Christopher Shumway as the coffee shop supervisor apparently lay dying in the employee bathroom.

One of the witnesses testified Shumway seemed angry as he served coffee on the night of the killing of Erin Sperrey. Another testified hearing a scream.

Shumway, 20, is accused of beating and kicking Erin Sperrey and then leaving her to die while he continued to serve drive-through customers on Jan. 2, 2005.

Shumway, who’s charged with murder, robbery and gross sexual assault, is using an insanity defense but prosecutors contend he went to considerable trouble to cover up the crime. He wanted to steal money and the victim stood in the way, they said.

Shumway, who has suffered from mental illness for years, does not remember anything from the night of the attack, said defense attorney Brad Macdonald. “He’s a man who has lived a long life of abuse,” he said.

The trial got under way with opening statements on Monday and continued Tuesday in Aroostook County Superior Court. Justice E. Allen Hunter was hearing the case without a jury at the request of Shumway’s lawyer.

Sperrey, 20, was strangled, beaten and kicked, and her face had boot marks on it, Dr. Michael Ferenc, the state’s deputy chief medical examiner, testified Monday.

She died from an injury to her heart that caused blood to fill the heart sac; the pressure buildup caused her heart to stop beating within 30 minutes, Ferenc said.

Afterward, Shumway stuffed Sperrey’s body in her car and then drove south for 120 miles until he spun out on Interstate 95 in a snowstorm, prosecutors said. He abandoned the body and the car, and hitched a ride to a Bangor motel, where he was arrested.

Experts from the state crime lab testified Monday that they found Sperrey’s blood on Shumway’s clothes and footwear, as well as in the restaurant. Semen swabbed off Sperrey’s body was consistent with Shumway’s, experts testified.

The victim’s family has said that Shumway had a crush on Sperrey and had asked her out on dates several times before she was killed.

Members of Shumway’s family have said that Shumway suffered psychological problems and that they had repeatedly sought help for him.

Macdonald said the state has oversimplified the case. “They seriously misjudged this complex situation,” he said.

Assistant Attorney General Andrew Benson told the judge in his opening statement that Shumway may have suffered psychotic episodes, but his actions demonstrate that he was not criminally insane at the time of the attack.