Samsung conglomerate leader Jay Y. Lee is set to stand trial on Tuesday charged with the unlawful use of a controlled substance, as legal woes continue to haunt the executive even after his release on parole in August following a bribery conviction.

Lee's release had raised market watchers' expectations of a flurry of major decisions at crown jewel Samsung Electronics Co Ltd and its affiliates, including the location of a $17 billion chip factory being planned in the United States.

But Lee is having to refocus on his legal troubles, with the Seoul Central District Court scheduled to hold its first hearing of a case in which Lee is suspected of receiving propofol - a sedative used in anaesthesia - outside of medical purposes at a clinic in Seoul.

Under South Korean law, the recipient of a controlled substance deemed to have been administered illegally is liable for prosecution, as well as those who administered the drug.

Lee's counsel has said his use was hospital treatment and not unlawful. Clinic staff, who are being tried separately, have denied wrongdoing.

Prosecutors were first made aware of the matter in 2020 but were advised to drop their investigation in March 2021 by an independent panel reviewing prosecution probes. They continued to seek the maximum fine as recently as June before another police report of sedative use led the court to order a trial.

The crime carries a maximum sentence of five years in jail or a maximum fine of 50 million won.

Legal experts, however, said they do not expect the maximum penalty should Lee be found guilty because propofol is less likely to be misused than many other controlled substances.

Lee was convicted in January of bribery and embezzlement and sentenced to 30 months in jail - including a year served before his sentencing. He was paroled in August, with the presidential office calling for public understanding, citing hope that he will help the country produce "semiconductors and vaccines".

After his release, Samsung said it would invest 240 trillion won in the next three years in fields such as chips and biopharmaceuticals. Lee himself has kept a low profile.

Lee is simultaneously on trial accused of stock-price manipulation and accounting fraud related to the $8 billion merger of two Samsung firms in 2015, with hearings held weekly.

($1 = 1,199.6500 won)