A Prince George's County jury found a Hillcrest Heights man guilty of first degree murder last night for bludgeoning his wife to death with a sledgehammer at the Hampton Mall shopping center on April 21.

Francis R. Holley, 38, had pleaded not guilty by reason of insanity, but jurors took only 30 minutes to find him both sane and guilty of killing Dorothy L. Holley, 38.

According to testimony at his trial, Holley had been having serious disputes with his wife since 1979, and a divorce hearing was to have been held one week after the killing. Prosecutor William Shockley and defense attorney Gerald Baker agreed that Holley suffered some degree of paranoia and suffered delusions that his wife had been having affairs with numerous people, including a county police officer.

But Shockley maintained that Holley, a construction worker, was fully aware of the criminality of his actions and was sane when he undertook them. "He was a man in control," Shockley told the jury. "He was a controlled man, but a very angry man, a very vindictive man."

Defense psychiatrists maintained that Holley could not appreciate the significance of what he was doing when he killed his wife. Greenbelt psychiatrist Dr. Harvey Resnick said Holley suffered from "a major mental illness," which he diagnosed as "matrimonial paranoia."

Holley, who has been held without bond, is scheduled to be sentenced by Circuit Judge William H. McCullough on July 8. He could receive life in prison.