One sheriff in Virginia is under investigation for allegedly bringing the wives and girlfriends of jail inmates to rented houses for his own sexual pleasure and that of his political supporters.

A second Virginia sheriff is accused of embezzling several thousand dollars from the garnishee fund handled by his department.

A third is being investigated by a special grand jury for alleged inability to run his department. "The sheriff," according to a policeman close to the investigation, "just doesn't pack the mental gear to do his job."

Sheriffs in Virginia, an institutin since 1634 when they first were appointed by royal proclamation, have been the subject of a "steady stream" of investigations in recent years, according to the Virginia State Crime Commission.

The sheriffs of Fairfax County,Virginia Beach. Henrico, Henry and Pittsylvania Counties are being investigated currently by the county prosecutor, a special grand jury or state police.

In the past year, sheriffs in Norfolk, Chesapeake, and Shenandoah, Hanover and Smyth counties also have been the subjects of investigations.

Some of the state's 126 elected sheriffs angrily complain that the charges against them are brought by opponents seeking headlines or revenge.

Fairfax County Sheriff James D. Swinson, whose department has been under investigation for six months, said recently the probe amounts to "a bunch of bull - and my only statement is put up or shut up."

But many Virginia law enforcement officials, prosecutors and legislators said they believe today's sheriff often is beset by shifting public attitudes and new responsibilities with which some are ill-equipped to deal.

Allegations of corruption and inefficiency against urban and rural alike have led to questions about the usefulness of an elected sheriff.

"The sheriff is an anachronism," said Judson W. Collier, the commonwealth's attorney from Henrico County near Richmond. "In this and other urban counties the sheriff is nothing more than an administrator. I don't think it takes an elected official to do that job."

In Virginia's rural areas, where 80 of the state's 126 sheriffs are the primary law enforcement officers, the sheriff has "no checks and balances like a police chief who must answer to a city manager or county executive," said James D. Stinchcomb, chairman of the department of administration of justice and public safety at Virginia Commonwealth University.

"Many sheriffs find themselves with power they never dreamed existed. No one watches the sheriff but the citizens who elect him, and they don't watch the day-to-day operations."

Sheriffs accustomed to an acquiescent electorate, according to A. L. Philpott, a member of the state crime commission and a Democratic delegate to the General Assembly from Henry County, have had trouble adapting to changing public attitudes about the integrity of elected officials.

"Most folks 15 or 20 years ago took the attitude that the sheriff just wouldn't do anything wrong. In those days, a trusty in a jail would wash the sheriffs car or run an errand for him and no one would care. But the public is not accepting that kind of thing anymore, and old-time sheriffs are getting into difficulty."

Attorney General J. Marshall Coleman, Virginia's top law enforcement officer, refused to comment about the number of investigations of sheriffs undertaken now or in the past by his office.

Coleman also declined comment about the number of sheriffs in the state who have been convicted of criminal offenses or have been forced to resign because of criminal charges.

Packing political influence in their localities and in the General Assembly, the sheriffs have managed to keep talk about reforming their constitutionally mandated office from becoming anything more than talk.

Their supporters recently crushed a proposed bill that would have given state police greater authority to initiate investigations in rural areas.

Still, several sheriffs interviewed across Virginia agreed that changing standards of conduct expected by the public have caused sheriffs grief.

"You can't run an office for 300 years one way and expect everyone to reverse themselves right away," said Arlington County Sheriff J. Elwood Clements, who has been in office for 20 years. "Some of the things that my father (who was also an Arlington County sheriff) did would absolutely be out of line now, like using immate labor to wash cars and janitor around the courthouse."

Sheriff S. Joseph Smith of Virginia Beach, who is under investigation by a special grand jury for incompetence and irregularities in running his jail, said that sheriffs have to be more careful than ever before.

"Four or five years ago," Smith said, "you could use county motor vehicles to campaign in and still get a mileage allowance. You used to be able to entertain your friends with food from the jail. You used to be able to give a friend a cup of coffee. You can't do it anymore."

Smith, 57, a sheriff who maintains a high public profile in Virginia Beach by personally directing traffic at the funerals of prominent residents, was elected in 1973 as a "reform" candidate. He replaced a sheriff whose jail had been criticized frequently by the Virginia Department of Correction. The former sheriff involved Virginia Beach in a federal civil rights suit by ordering that every inmates, including those in jail for one night, have his head shaved.

A patrol car trooper for the Virginia State Police for 27 years, Smith has presided over the construction of a $5 million jail completed this spring. He was reelected last year by a 3-to-1 margin and he calls himself "the biggest vote-getter they have around here."

His department employs more than 80 deputies and has an annual budget of $1.2 million. On weekends when the city is crowded with transient youths who come to enjoy the beach, drugs and alcohol, the jail houses as many as 200 inmates.

"Sheriff Smith just can't handle his job," said one prosecutor in Virginia Beach. "It is a job for an administrator, and he just isn't an administrator."

Smith's department has been under investigation since last November when two inmates, who had smuggled money into the jail in the lining of their clothes, were allegedly robbed by other prisoners of $1,700.

Since then, the sheriff has been chided by the Virginia Beach City Council for paying a suspended deputy his full salary for five months in violation of a city ordinance. Out of his own pocket, Smith reimbursed the city the $1,300 paid to the deputy who had been suspended for allegedly allowing marijuana in the jail.

Smith's department made a background check earlier this year of a woman who applied for a job as a jail matron and failed to discover that she was a fugitive on a heroin charge. The woman was arrested by city police before she could be hired, and a computer check found she was a fugitive from New Jersey.

Last fall, Smith ruined the "chain of evidence" in the prosecution of an inmate found with marijuana, according to Commonwealth's Attorney Andre Evans.

Evans said Smith took the marijuana from an inmate, stuffed it in a brown paper bag and put it in his desk drawer. Smith's action violated one of the most "elementary" principles of police procedure, Evans said, by making it impossible to prove that the marijuana in the sheriff's desk was the same drug taken from the prisoner. Normally, drugs are sealed in special bags. The inmate from whom the drugs had been taken could not be prosecuted, Evans said.

"Smith is not derious; he just doesn't know any better," said a Virginia Beach police officer of the incident.

In an interview at the conference room in his new jail, Smith was asked why he had stored the marijuana in a drawer. The sheriff refused to respond to the question and ended the interview by getting out of his chair and leaving the conference room.

Some sheriffs, including Smith, who have come under public scrutiny for misuse of prisoners and other alleged improprieties blame prosecutors and the press for nit-picking and political motivations.

Henrico County Sheriff W. P. (Bill) Selph says that his accusers don't want him to be re-elected and claims that the press had used smear tactics against him.

Selph is the subject of a Virginia State Police investigation ordered by Attorney General Coleman, according to a source close to the investigation, that is looking at allegations that Selph made improper sexual advance toward femal employes, that he illegally "farmed out" his deputies for private security jobs and that he misused for political purposes money from a "flower fund" to which his deputies were required to contribute.

Selph, a second-term Democrat, denies the allegations, calling them ridiculous" and charging that the attorney general and Henrico Commonwealth's Attorney Collier, both Republicans are attacking him because he is up for reelection next year.

The sheriff in Virginia is a constitutional officer, similar to the commonwealth's attorney, elected every four years. A candidate for sheriff need not have any background in law enforcement, although most do, according to John W. Jones of the Virginia State Sheriff's Association.

In rural areas, according to Philpott and VCU's Stinchcomb, most sheriffs perform a vital function, administering relatively small departments and keeping the peace.

In urban areas, however, Philpott and Stinchcomb and several commonwealth's attorneys agree that popular election for a larger administrative job doesn't make sense. "Let's face it," Philpott said, "the popular boy is elected every time. In urban areas he may have tremendous administrative responsibilities. He can get himself involved in a lot of trouble."

According to a source in the state crime commission, sheriffs in the past have most often run into legal problems by misusing funds from jail vending machines or canteens, by using inmate labor for personal gain and by overcharging when deputies are used to transport mental patients to state hospitals.

In southern Viriginia near the North Carolina border, Sheriff C. P. Witt of Henry County has been charged with those three criminal offenses. Witt also faces a felony charge of embezzling from the garnishee fund that his department maintains.

Special prosecutor J. Patrick Graybeal said Witt, a 14-year veteran of the office, also has been charged with having his deputies operate a profit-making bus line while on duty, having deputies draw two paychecks - one from the state, the other from private firms - for the same work, and with giving partly used sheriff's department automobile tires.

Witt could not be reached for comment.

Asked if they see any conflicts between politics and law enforcement or if they think it unwise for voters to elect an inexperienced man as sheriff, sheriffs interviewed across the state invoke history, democracy and the wisdom of the people.

Fairfax Sheriff Swinson, serving his fourth term, said, "The electorate has an uncanny way of eliminating from public office those who shouldn't be there."

Virginia Beach Sheriff Smith said, "An elected sheriff is more receptive to the people. Every chief of police is a prisoner within his own self."

Arlington County Sheriff Clements said that if a sheriff doesn't "keep up with the people he won't be around very long."

But Stinchcomb disagrees. "I just don't think the public cares about sheriffs. If they happen to know the sheriff's name that is the best they can do. The average person in an urban area doesn't even know what the sheriff is supposed to do."