Paul Wersick "heard a loud explosion" at the instant tax assessor George Angerman Jr. was shot to death, and in the moment that followed, he saw Angerman "had blood on his face," a psychiatrist testified yesterday at Wersick's murder trial.

Dr. Bryant Wedge told the jury that seconds before the shooting, Wersick 'had some change in his consciousness . . . he felt he could hear his own breathing, hear auto sounds, smell exhaust smells."

That description of events by Wersick, who has pleaded innocent by reason of insanity to the murder charge, fits so closely with classic cases of mental disorders that the 16-year-old could have been lying, Wedge said when pressed on this point under cross-examination.

"I don't think a board-certified psychiatrist could carry on such a masquerade," Wedge told Assistant State's Attorney Michael Mason.

Earlier, the Washington psychiatrist told the jury that Wersick's victim, a male stranger, "somehow represented Wersick's father," a father who had left Wersick's mother before the youth was born.

Wersick once described his father as a "no-good bum, a gutless bastard," in an interview with Wedge, the psychiatrist said. "There was an element of seeking revenge against a father he had never known but had sharp and hostile feelings toward," Wedge said of the crime.

Wedge, called to the stand by defense attorney J. James McKenna, testified that Wersick suffers from three mental disorders, the most serious of which is "explosive personality." A person with this disorder, he said, "loses control of his faculties, blows up, commits serious acts with his not being able to know what he is doing." Wersick was suffering from this when Angerman was killed, the psychiatrist said.

Wersick is accused of robbing, then killing Angerman, who was found last July 11 with his mouth bound by a Boy Scout neckerchief, his left wrist tied with a rope.

An unusual Saturday session was held in Montgomery County Circuit Court in an effort to speed completion of the trial because the jury is sequestered.

Wedge testified that during the shooting, Wersick's mental state met Maryland's legal definition of insanity lacking "substantial capacity to appreciate the criminality of his conduct or conform his conduct to the requirements of the law."

During the robbery, however, the youth "did consider what he was doing was wrong, but at the level of a 4 or 5-year-old," Wedge said. "It is not reasonable to think a 4 or 5-year-old can make reasoned judgments," he added.

Wedge stated under questioning by prosecutors that a legally sane criminal "who commits an act for gain makes effort to carry it out so he won't be detected."

"Killing the only eyewitness, wouldn't that be consistent with the acts of a same man?" the prosecutor asked him.

"Yes," Wedge answered.

"Who were the only eyewitnesses?" Mason asked.

"Paul Wersick, and the victim, Mr. Angerman," the psychiatrist answered.

But Wedge repeated several times his opinion that Wersick "wanted to be caught" for the crime.

"Personally, I think it was a great relief to him," Wedge said of Wersick's arrest last July, less than a week after the killing.

Wedge had testified that Wersick, who wanted to have friends but didn't know how to relate to others, lived in constant fear of his potential for "rage and explosiveness."

"He would move toward people, then fearing . . . his own rage, he'd move back," the doctor said.

"That's why I think he is not dissatisfied with the idea of being put away for a long time."