LOS ANGELES: A US court on Thursday overturned rulings that squashed drugs-related convictions against late model Anna Nicole Smith's boyfriend and most convictions against her former psychiatrist.

Howard K. Stern and Khristine Eroshevich were convicted in 2010 of conspiring to provide drugs to the former Playboy model, who died of a drug overdose in 2007.

But at a sentencing hearing last year, Los Angeles judge Robert Perry dismissed Stern's two conspiracy convictions, citing insufficient evidence, and three of Eroshevich's four convictions.

The 2nd District Court of Appeal, however, ruled Thursday that Perry erred in Stern's case, saying he could allow a new trial, dismiss the convictions on other grounds or sentence him based on the original convictions.

In Eroshevich's case, the judge could order a retrial or dismiss the convictions on other grounds, it said in a 34-page ruling by a three-judge panel.

Stern, Smith's longtime lawyer and boyfriend, was found guilty in October 2010 on two conspiracy counts relating to using a false name to secure prescription drugs for the model.

Eroshevich was convicted of four counts of fraudulently obtaining medication when prescribing drugs under false names to the starlet, who died in a Florida hotel room in February 2007 at the age of 39.

The panel said there was “evidence Mr. Stern knowingly participated in conduct designed to avoid detection” and that Stern knew Eroshevich's prescriptions were written in names other than Smith's true name.

“His knowledge and involvement was such the jury could reasonably conclude Mr. Stern, a lawyer, knowingly participated in the ongoing illegal practice of securing illegal prescriptions,” they said.

An autopsy following Smith's death, a worldwide media sensation at the time, found it was due to a lethal cocktail of anti-anxiety medication, methadone, antibiotics and other prescription drugs.

It came just months after her son, 20-year-old Daniel, died from an overdose in the Bahamas in September 2006.

Born Vickie Lynn Marshall, Smith married Texas billionaire oil tycoon Howard Marshall in 1994, after meeting him earlier when she was working at a strip club. She was 26 at the time and he was 89.

The platinum blonde was regarded by some as one of the world's most desirable women in the 1990s when she replaced supermodel Claudia Schiffer as Guess Jeans model. She was also Playboy magazine's Playmate of the Year in 1993.