D.C. police officer Leroy T. Smith Jr. was called last Feb. 17 to a Northeast Washington supermarket where the store manager was holding three boys whom he had caught stealing a 99-cent bag of potato chips and a 35-cent bag of cookies. The manager did not want to file charges against the youths, who were 12- and 13-year-olds, but he turned them over to Smith and his partner.

After a couple of hours of trying to handle the matter, Smith decided one of the 13-year-olds needed discipline, and with the permission of the youth's guardian, he says, "I put him across my knee and whomped him four times."

The spanking was a tactic the 12-year police veteran had used before. It had worked for him in the past, and he still remembers the impression it left when a police officer did it to him once when he was a child.

The 32-year-old Smith says he will not be spanking anyone anymore.

Because of that incident, Smith was taken off the streets for five months, was investigated by the U.S. attorney's office, and now faces disciplinary action from the police department.

Police department regulations forbid police officers from spanking children even if the parents or guardians give permission. "We're not supposed to touch a child," said Deputy Chief Ronal D. Cox, who heads the 1st District, where the incident occurred. "It was an unlawful touch."

"The officer was wrong," said Police Chief Maurice T. Turner Jr. "Officers can recommend that parents discipline a child. They can counsel kids and warn them. If the child is in need of supervision, you send him to the proper authorities. We have no business spanking kids even though some of them deserve it."

Smith believes spanking may be just what some kids need, a useful enforcement tool that no longer is tolerated from police officers who have to devise all sorts of nonarrest techniques to deal with minor problems they encounter on the streets.

"I was trying to discipline this child to turn him in another direction," Smith said. "Here's a kid, if we don't do something to turn him around, by the time he is 16 he is going to be in serious crime."

Smith said he doesn't believe the spanking was unreasonable. "I did him just like I do my own," said Smith, who has a 12-year-old son and 13-year-old daughter.

It was 9 a.m. last Feb. 17 when Smith said he got a radio call to report to the Safeway store at Sixth and H streets NE. In an interview this week, he gave the following account of what followed. Other law enforcement officials and the youth's guardian confirm the account.

When Smith and his partner reached the store, the manager told them he did not plan to file charges. The youths told Smith that they had not been home since the previous day when they had gone to a movie and then had ridden buses all night, transferring to different buses when they reached the end of the lines.

Since it was 9 a.m. and a school day, the youths were truants. Smith and his partner decided to take the three to the 1st District youth division.

At the station, the youths' parents were called. Two youths' parents said they were coming to get their sons. Smith talked to the third youth's guardian, who said the youngster would not go to school, would not stay at home and was always getting into trouble. The guardian said the 13-year-old needed some discipline. "If you can do something with him, go ahead," his guardian said.

Smith tried to counsel the youth at the station: at one point, he asked him to write an essay on what he wanted to be when he became an adult.

During the conversation, the 13-year-old mentioned several times that he wanted to go to the country and get a job. Smith said he then posed a problem -- something he has done with his own children on many occasions.

Smith said he told the youth that he would either be rewarded or punished depending on his answer.

The problem, Smith said, was, "Would it be smarter for a 13-year-old, with little education, little training, no money, no idea of where he was going and without his parents' permission to go off to the country and get a job, or would it be smarter for a 13-year-old to go home, stay in school and get an education and then when he is grown, go off to the country?"

Smith gave him five minutes to think about it. The answer came back, go to the country. Smith said that was the wrong answer and told him to think about it again. If he gave the wrong answer again, Smith warned he would give the youth a punishment "he wouldn't forget."

When he asked the youth for his answer again, the 13-year-old said he wanted to go to the country. Smith then spanked the youth, who cried loudly.

Two officials rushed out of a nearby office and asked Smith what had happened. Smith said he had spanked the youth.

Police officials called the youth's guardian. "I didn't know what had happened," the 13-year-old's guardian said this week. "I didn't want to go and get the officer in trouble. All I wanted was for the youth to get some help."

" The youth is the type of child who doesn't want to be disciplined by anybody," said his guardian, who has been taking care of him since he was 11 months old. "The only thing wrong with spanking him is it doesn't do any good." She said the 13-year-old now is in a home for troubled youth.

A psychiatric evaluation of the youth done when he was 9 years old reports: "He is impulsive, disobedient, not responsive to punishment or spankings, stays out all hours, doesn't behave well in school . . . His problems are serious and he needs considerable help to resolve them."

Though the youth's guardian did not pursue any charges against the officer, the police department conducted its own investigation.

Cox described Smith as "a good officer" whom he hated to penalize for "a momentary lack of discretion or judgment." However, he said the department's policy forbids spanking children as well as any corporal punishment against adults. "We are limited in the amount of force we can use," Cox said.

The U.S. attorney's office investigated and reviewed the case, but declined to prosecute, officials said. Cox said the matter has been forwarded to the police department's disciplinary review officer, who could fine or fire the officer.

Smith, who as a child growing up in a Northeast Washington public housing project was spanked by an officer one day for shooting craps, says he has learned his lesson. "I won't be touching anyone from now on."