In an article in Wednesday' editions it was incorrectly reported that Fairfax County Deputy Sheriff Carl Peed is the brother-in-law of Sheriff James D. Swinson. Capt. Peed is Swinson's son-in-law.

Fairfax County Sheriff James D. Swinson, describing himself as "a tough old goat" who wanted to "let it all hang out," told the county Board of Supervisors last night that he had no prior knoweledge of any illegal activities in his department and he runs the best jail in Virginia.

Commonwealths' Attorney Robert F. Horan, who has been investigating Swinson's department since February for alleged misuse of jail inmates, told his supervisors his probe has uncovered "widespread use of prisoners by high-ranking deputies outside the jail" for the private purposes of the deputies.

Horan, speaking in a room packed with sheriffs deputies who showed up to cheer Swinson, said he found no evidence that the sheriff has committed a criminal offense.

After listening to Swinson and Horan, the board voted untnimously to ask the county executive to look into the possiblity of conducting an independent management study of how the sheriff's department is run.

At last night's session, scheduled by the supervisors last month on a 5 to 4 vote. Swinson was forced to answer questions ranging the propriety of hiring and promoting his brother-in-law to whether he had ordered his deputies not to cooperate with Horan's investigation.

Supervisor Alan H. Magazine (D'Mason), who first requested last night's meeting with Swinson and who dominated the questioning of the sheriff, asked Swinson if it was "good for the system" that he hired and promoted his brother-in-law, Capt. Carl Peed.

Swinson said that Peed, who was hired as a corporal in 1974 and received three promotions in three years, was promoted because he was "that good" and that Fairfax County "was lucky to have him."

Informed sources in the sheriff's department said yesterday that Peed's rapid advancement from corporal, with an average salary of about $17,000 to captain, with an average salary of about $25,000, was unusually fast.

"I don't have any problems with that (Peed's promotion) at all," Swinsin said.

Swinson said he "certainly has not told anyone not to talk to (Horan's investigators)." The sheriff refused to comply with a request by Supervisor James M. Scott (D-Providence) that he issue a written order to his deputies, telling them to cooperate with that investigation.

"Mr. Horan has had all kinds of stool pigeons running to him," Swinson said. He said he could not stop anyone from going to the prosecutor and that it is "too late" to issue a written order to his deputies because "certain animosity have build up."

Horan told the supervisors he had been informed by many deputies in his department that they were afraid to cooperate in the investigation "under pain of being fired."

Swinson closed his remarks to the board last night by saying he will have "no further statement" on the allegations that have been made against his department.

"I am finished, period, thank you," the sheriff said. He walked out of the board room as his deputies giving him a standing ovation.

Outside, Swinson shook the hands of deputies who had come to support him and he told them to "hang in there" and asserted, "We're going to make it.

Last night's questioning of the sheriff was opposed by four members of the board: one of them, Marie B. Travesky (R-Springfield), took the inquiry as an opportunity to present what she called "a little commercial" for Swinson.

Travesky said she had spoken in the past week with several high-ranking officials from the Virginia Department of Corrections and that "they couldn't say enough good about the sheriff."

Travesky quoted one corrections official as saying he "wishes all jails were as well run as in Fairfax County."

The controversy on the board over inviting the sheriff, who is a Republican, to answer questions about his department has split along party lines, with the exception of Supervisor Joseph Alexander (D-Lee), who called the inquiry "an inquisition."

Last night Supervisor John P. Shacochis (R-Dranesville), in a reference to political motivation, asked Horan, a Democrat, why he has let his investigation drag on for more than six months.

"We will shut down the investigation," Horan replied, "When I feel everyone has been heard from."

Horan said he began looking at the sheriff's department last December after Swinson's chief jailer, John O. Feehan admitted that he had used a jail inmate to pour concrete at the sheriff's home. Feehan denied under oath that he had used the inmates at the sheriff's home, but later recanted his testimony.

Swinson denied any knowledge that inmates were used at his home and Horan said he has no evidence that Swinson knew anything about it.

Horan said his investigation has uncovered "extensive" criminal misuse of inmates during 1974, 1975 and 1976 and one instance in 1977.

Horan has said the crimes his investigation has uncovered are all misdemeanors that occured more than a year ago and that, under the statute of limitations, he cannot prosecute those responsible.

Swinson said last night he will not take administrative action against any of his employes until he is "absolutely satisfied" in (his) own mind that a criminal act did occur."