A doctor who is currently under investigation for illegally administering the drug propofol, claims that while he did inject South Korean R&B singer Wheesung with the drug, it was a purely legal procedure.

The doctor testified that the singer was innocent in Thursday's hearing, according to the publication eNEWS.

"The army prosecution acquitted all charges on the Wheesung case," Wheesung's attorney Son Su Ho of Giant Law Firm. 

"[Several witnesses testified] he did not receive injections of the psychotropic drug illegally. Even the doctor who is on trial for administering illegal doses of propofol testified that Wheesung did not use the drug illegally."

Mainly used an anesthetic, propofol is perhaps best known for causing Michael Jackson's fatal overdose in 2009, when it was mixed with the psychoactive drug benzodiazepine.

Last month, South Korean Army prosecutors alleged Wheesung was administered propofol numerous times during a vacation, according to the Korea Star Daily.

They revealed that the army has investigated the singer two previous times for abusing the drug.

Wheesung's first incident reportedly involved dermatologists and psychiatrists around Seoul in 2011.

At the time the reports came out, Son dismissed the propofol abuse utter nonsense.

"It's not true at all," Son said.

"We've currently prepared proof that he only administered [the drug] for treatment purposes," he said.

Media speculation while Wheesung was questioned by army investigators in April and May led to intense speculation in the media.

The coverage hit a fever pitch when news service JTBC quoted an anonymous source claiming the 31-year-old R&B singer ordered "hired thugs" to kill her after she saw him after she saw him receiving propofol injections while he was serving in the army.

"I saw [Wheesung receiving propofol injections] multiple times a month," the source said.

"Just in the army, I saw him doing it five to six times over a span of two weeks. He wanted to keep me silent, so he even hired thugs. I was told that he told them to kill me."

Son claims he and his client are disgusted at the unfounded speculation in the media.

"We're shocked that [these negative media reports have come] out while investigations are still ongoing," Son said.

"Soon, everything will be revealed, and Wheesung will be cleared of his accusations."

The singer claims he used propofol to treat a herniated disc.

"Wheesung had propofol administered to him as a painkiller," the lawyer explained.

Wheesung, whose real name is Choi Hwee Sung, is currently serving out the end of his two years of mandatory national military service as an army training officer in the city of Nonsan.

The singer will be formally discharged from the army in August.

After his prediction of legal victory came true, Wheesung's lawyer was, as one would expect, quite pleased with the outcome.

"The incident came to a close with a just conclusion," he said. "It concluded with good news."