The Washington Post incorrectly reported on July 27 that Howard Chasanow testified on Gary Lee Hyer's murder trial. The psychiatrist from Clifton T. Perkins Hospital who testified for the state was Dr. Ido Adamo. Chasanow was the presiding judge in the case.

A 26-year-old Suitland man who admitted killing a former girl friend while under the influence of the drug PCP Christmas Eve was convicted of second-degree murder yesterday by a Prince George's County Circuit Court jury.

The jury, which heard testimony that the defendant, Gary Lee Hyer of 4692 Homer Ave., was unable to form a premeditated intent to kill Diana Lynn Knack because he was intoxicated with PCP at the time of her slaying, acquitted Hyer of a first-degree murder charge.

Acording to testimony, PCP, one of the names for the animal tranquilizer phencyclidine, can induce temporary psychosis in some humans who use it. Hyer had used PCP regularly for several years, according to defense witnesses.

Hyer's attorney, Louis J. Mantucci, asked the jury to find Myer innocent of any murder charge by reason of insanity.

Dr. Brian Crowley, a psychiatrist at the Potomac Foundation who examined Hyer for the defense, testified that Hyer's long use of PCP could have induced a state of "toxic psychosis." Each use of the drug, Crowley said, could have caused Hyer to become psychotic, but he would have remained normal when not under influence of the drug.

Dr. Howard Chasanow, a psychiatrist at Cliffon T. Perkins State Hospital, testified for the prosecution that while Hyer suffered from "a mental defect," his use of PCP did not necessarily prevent him from thinking rationally.

Mantucci said the jury's verdict does not necessary mean that the killing was found unpremeditated because of the use of PCP. The verdict simply indicates there was unsufficient evidence of premediation, he said.

Mantucci said, however, that because his defense of Hyer rested principally on Hyer's use of PCP the morning of the killing, the verdic "broaches important problems" about PCP's influcence on those who commit crimes. He said Hyer's conviction indicates that even regular use of PCP may not be used as the basis for insanity defense.

But, Mantucci said, "the case shows the need for doctors to determine just what the effects of this drug can be over a long period. No one is sure what its effects are, and it is important to know whether it can cause prolonged insanity."

Hyer faces a prison term of up to 30 years on the second-degree charge, according to Assistant State's Attorney Charles P. Strong. Sentencing has been set for Sept. 1.

After Hyer was arrested by police Feb. 2, Strong said, he admitted killing Knack.

Hyer told police he killed Knack after an argument in her Forestville apartment, and lead investigators to a frozen stream near Great Falls, where he had dumped the body, Strong said.