The Maryland Court of Appeals yesterday overturned the conviction of a Silver Spring animal researcher who had been found guilty of cruelty to a research monkey in a 1981 case that involved the first prosecution of a scientist under the state's anti-cruelty statute.

The state's highest court, in a unanimous opinion, ruled that Maryland's anti-cruelty law does not apply to federally funded research projects because such projects fall under the federal Animal Welfare Act, which sets standards and procedures to insure humane treatment of research animals.

The decision marks the culmination of a case that had attracted national attention after Montgomery County police staged an early-morning raid on the Silver Spring laboratory of Dr. Edward Taub and seized 17 research monkeys in September 1981. The raid resulted from information provided to police by Alex Pacheco, a member of an animal welfare group who infiltrated Taub's lab as an aide and accused him of mistreating the animals.

Throughout the legal proceedings, Taub denied mistreating the animals and said they were being used in invaluable experiments on the effects of damage to the central nervous system.

"I am delighted to be exonerated in this way," Taub said yesterday. "From the beginning I have said there was nothing improper being done in my laboratory and this ruling confirms that. But more than that, I am delighted on behalf of science. The earlier ruling in my case had a very chilling and improper effect on legitimate researchers."

Taub originally was accused of cruelty to all 17 monkeys seized in the raid. But at his first trial in the county District Court, he was convicted only on six counts of failing to provide proper veterinary care to six animals.

When he appealed this conviction in county Circuit Court, the jury found Taub guilty of failing to provide proper veterinary care for one monkey, Nero, during experiments at the Institute for Behavioral Research, where Taub was the principal investigator.

Taub hailed his acquittal on the five other counts as "vindication for my research."

Yesterday, Pacheco, head of the Washington-based People for Ethical Treatment of Animals, said the ruling was a "major setback," at least at the state level, for animal welfare advocates who had hoped that the original conviction would set a nationwide example.

"The court decided the state anti-cruelty laws do not apply to any research with federal money," Pacheco said. "The situation must be addressed at the federal level."