NORTH DAKOTA, USA. (AP) — A jury yesterday acquitted a North Dakota surgeon accused of drugging his wife and raping her while she was unconscious.

Dr Jon Norberg lowered his head and exhaled as the verdict was read in the Fargo courtroom. His brother Doug Norberg, a lawyer who assisted the defence, started crying.

Norberg, 42, could have faced up to life in prison if convicted of gross sexual imposition and reckless endangerment. The jury, which could have convicted him on lesser charges, deliberated for about four hours before finding the orthopeadic surgeon not guilty.

“It has been surreal. It’s been surreal the whole time,” Norberg said outside the courtroom.

His attorney, Robert Hoy, said he was confident his client was innocent.

“That made it easy to be his lawyer,” Hoy said.

The jury would have been allowed to consider lesser charges on each of the two counts if Norberg had been found not guilty.

Prosecutor Gary Euren said he believed it was a strong case and said he wouldn’t do anything differently.

“It was a difficult case,” Euren said. “Obviously from the beginning it was basically a ‘he said, she said’ case, and those are very difficult, especially with juries.”

Norberg’s estranged wife, Dr Alonna Norberg, didn’t attend most of the nine-day trial, but some of her family members did. None of them were on hand yesterday to hear the verdict.

Euren, when asked what’s next for Alonna Norberg, said he didn’t know and hadn’t had the chance to speak with her.

Alonna Norberg, who is a paediatrician, testified during the trial that her husband injected her with propofol on the night of June 16, 2011, and that she passed out. She said she awoke to him forcing her to perform oral sex.

The Associated Press typically doesn’t identify the victims of alleged sex crimes, but Alonna Norberg has spoken publicly about the case, including to deny her estranged husband’s story that she agreed to take the medication as part of treatment for a debilitating disease.

Jon Norberg’s attorneys argued that the rape claims were bogus and that Alonna Norberg cooked them up to help her in her looming divorce from her husband and a child custody case. They said she feared she wouldn’t get custody of the children because of an alleged addiction she had to prescription drugs and because of mental health issues.

Jon Norberg testified that he injected his wife with propofol regularly over an 18-month period to treat her chronic pain condition. Alonna Norberg said her husband called the drug by its brand name, Diprivan, and that she wouldn’t have taken it if she had known it was propofol, a powerful anaesthetic that gained notoriety during the investigation into pop star Michael Jackson’s death.

Dr Steven Shafer, a professor of anaesthesia at Stanford University who was the key witness in the case against Jackson’s doctor, also testified in the Norberg trial. He told jurors that Jon Norberg wasn’t qualified to administer propofol and had put his wife’s life at risk.

Norberg said he expects the verdict to have an impact on the divorce and custody issues.

“My intention is to spend time with my family and we’ll work it out so it’s fair so she will get to spend time with them as well,” he said.

The state Board of Medical Examiners has indefinitely suspended Jon Norberg’s licence. Prosecutors said Alonna Norberg did not want to see her husband criminally prosecuted or lose his ability to practise medicine, but she wanted him to stop giving her propofol.