The case of a former Fairfax County school psychologist who was charged two weeks ago with the sexual battery of a school-age boy has turned a spotlight on the sometimes conflicting issues of the rights of employes and the need to protect students. It also calls into question the options available to school officials who must deal with an employe who is suspected of criminal activity but has not been charged.

Fairfax County school policy, according to personnel chief R. Warren Eisenhower, is that any employe found by a school investigation to have abused children sexually will be dismissed. And the evidence needed is less than what a jury needs to convict in a criminal case, he added.

Yet, as early as 1981, Fairfax and Prince William County police say, they presented photos to school officials showing a man they identified as the psychologist in explicit sexual poses with a young boy.

The psychologist, Arthur S. Pomerantz, was not dismissed at the time; rather, he was placed on adminstrative leave twice and forced to resign in 1984.

Eisenhower has declined to talk about that case, but school officials announced last week that in the face of growing controversy over their handling of Pomerantz, they are conducting an investigation into why the psychologist was not fired earlier.

"I'm reviewing the process of how the school system handles these types of things so in the future everyone is assured they are handled in a proper way," school Superintendent Robert R. Spillane said. "I'm not saying it wasn't. It certainly looks bad publicly. We're on the defensive."

The case has stirred discord between two of the county's largest institutions -- its police force and its public schools.

Although county public safety officials have not criticized the school system publicly for its handling of the Pomerantz case, privately they contend that school officials did not cooperate fully in their 1984 investigation of Pomerantz. School officials maintain that they did cooperate.

Police sources say that school personnel officials gave the impression that their main concern was to avoid being sued by the psychologist.

Pomerantz could not be reached for comment, but his attorney, Mark E. Sharp, said that Pomerantz planned to plead not guilty to the charge.

The investigation of how the Pomerantz case was handled is being administered by county and school officials. Spillane, who left a comparable post in Boston to take the Fairfax job just two months ago, said he intends to issue a statement when the investigation is concluded.

Among the questions posed by the case:

*If there was enough suspicion of Pomerantz's activities for school officials to put him on paid leave for several months in 1981, as police and coworkers have reported, why was he allowed back into the system the following September?

*When he returned to work after the leave, why was he placed in an intermediate school rather than reassigned to a job that involved less contact with children?

*Were any agreements between school officials and Pomerantz reached when he resigned in 1984? If Pomerantz had applied for another job working with children, would Fairfax officials have given him a good reference?

Fairfax County school officials will not comment on the substance of the case while it is being investigated, but some have said that they take accusations against employes seriously.

Ordinarily, Fairfax school officials conduct their own investigation of charges, bringing in police if a crime is alleged and social services workers if abuse is alleged. Employes are put on leave with pay if the charge involves child abuse, Eisenhower said.

School officials contend that standards of proof are lower for a school investigation than for a police probe. If the school investigation turns up wrongdoing, officials ask the School Board to dismiss the employe, Eisenhower said. "If there's any suggestion they've been involved in something, we'll go for the dismissal," he said.

But police sources have said there was such evidence in the Pomerantz case. Prince William County investigators say that in 1981 they gave Fairfax school officials sexually explicit photos of a man they said was Pomerantz posing with a young boy.

In fact, said Prince William County police investigator W.P. Metheny, criminal charges were not filed only because police could not determine when the photographs were taken -- a requirement in criminal cases.

School officials say suspicions of criminal behavior are rare. No more than a half-dozen investigations of school employes for potential criminal charges have been conducted in the past five years, according to James Shinn, director of employment services for the Fairfax schools. Some of those employes have been fired without criminal charges being brought, he said.

Among the grounds for firing Fairfax employes are their bringing disrepute upon the schools, unprofessional conduct and drinking on the job.

Civil libertarians say the school system should not be allowed to fire an employe based only on an internal investigation of a criminal complaint. They cite employes' rights to a presumption of innocence and due process of law.

"Standards [in a school probe] are less protective of civil liberties than a full trial," said Barry W. Lynn, legislative counsel for the American Civil Liberties Union.

"It's always possible that when one's constitutional rights are fully protected, it's not as easy to prosecute people," Lynn said. "But we do presume people's rights of privacy and protection against unreasonable search and seizure will be upheld."

Pomerantz was hired by the county in 1965 after a fingerprint check turned up no history of a criminal record.