COLUMBIA, S.C. -- Now that Michael Phelps won't face drug charges, he can try to distance himself from a photo that showed the Olympian smoking a marijuana pipe.

A South Carolina sheriff decided Monday after a highly publicized investigation that he simply didn't have enough physical evidence to charge the 14-time gold medalist.

"We had a photo and we had him saying he was sorry for his inappropriate behavior. That behavior could've been going to a party," Richland County Sheriff Leon Lott said.

"He never said, 'I smoked marijuana.' He never confessed that," the sheriff said.

Phelps, who lost a major endorsement and faces a three-month competition suspension in the fallout from the photo, said he was ready to put the ordeal behind him.

"For me, it's all about recognizing that I used bad judgment and it's a mistake I won't make again," the swimmer said in a statement. "For young people especially -- be careful about the decisions you make. One bad decision can really hurt you and the people you care about. I really appreciate the support my family and fans have shown me."

The photo showed Phelps smoking from a marijuana pipe at a party in November when he visited the University of South Carolina.

Lott said authorities seized the marijuana water pipe, known as a bong, in the photo during the investigation but couldn't prove Phelps had smoked from it.

Holding a bong is not a crime, he said.

"They're sold in stores. We're kind of sending a double message," Lott said. "You can buy rolling papers at any convenience store in the world, but we're telling kids not to smoke dope."

Phelps didn't get through the scandal unscathed, though. USA Swimming suspended Phelps for three months in the wake of the photo, and Kellogg Co. said it would not renew its endorsement deal with him.

And while the swimmer won't face any charge, eight people were arrested during the investigation when a small amount of marijuana was found in raids on two homes. The bong was found in a car.

Seven people have been charged with simple possession of marijuana, which carries a maximum penalty of 30 days in jail or a $575 fine. Another person was arrested for driving under suspension.

The sheriff, known for his tough stance on drug crimes, said ignoring the photo would have sent a message of tolerance.

Phelps' "bad decision and the highly published photo placed me and the Richland County Sheriff's Department in a no-win situation. Ignore it and be criticized or address it and be criticized. I chose to do what was right," said Lott, a Democrat who was first elected in 1996.

Lott rose from patrol officer to captain of the narcotics division in the early 1990s. He was well-known in the county for wearing stylish suits like the drug agents on "Miami Vice" and driving a Porsche seized from a drug dealer.

The sheriff said the investigation involved two narcotics officers that logged 25 hours over about a week. He said the house where the November party took place and another suburban home near Columbia had previously been investigated for drugs.

His investigation was criticized in newspaper editorials, on talk shows and by defense attorneys who questioned whether the sheriff was being overzealous because of Phelps' celebrity status.

Even if the sheriff had the evidence needed, he acknowledged he could not force Phelps to return to South Carolina to face a misdemeanor possession charge.

One of the attorneys representing the three students arrested said the accused were all in their early 20s. Attorney Dick Harpootlian said the police kicked in the doors with guns drawn during the raids and found less than a cigarette's worth of marijuana in the house where the party was held. The other raid netted about four or five cigarettes' worth, Harpootlian said.

The lawyer expects his clients to either have the charge dismissed or for them to get a conditional discharge, which allows offenders to avoid punishment as long as they comply with certain conditions for six months and stay out of trouble.

"We hope these kids are treated the same as any other kids," he said.

The photo surfaced in the British tabloid News of the World on Feb. 1. The swimmer, who won a record eight gold medals at the Beijing Games, never disputed its authenticity.

Lott said the person who took the photo sold it for $100,000. He would not identify the photographer or say how he knew the amount.

The party occurred nearly three months after the Olympics while Phelps was taking a break from training.

This isn't the first embarrassing episode for Phelps after an Olympic triumph. In 2004, a few months removed from winning six gold and two bronze medals in Athens, the swimmer was arrested on a drunken driving charge at age 19. He pleaded guilty and apologized for the mistake.