Actor Bijou Phillips has filed for divorce, 12 days after her husband Danny Masterson was jailed for 30 years for rape.

Celebrity news website TMZ reports that 43-year-old Phillips filed documents to end her 12-year marriage in a Californian court on Monday (local time).

“Ms Phillips has decided to file for divorce from her husband during this unfortunate time. Her priority remains with her daughter,” her lawyer, Peter A. Lauzon, told TMZ.

“This period has been unimaginably hard on the marriage and the family. Mr Masterson was always present for Ms Phillips during her most difficult times of her life. Ms Phillips acknowledges that Mr Masterson is a wonderful father to their daughter.”

Masterson, a former star of That ’70s Show, and Phillips married in 2011. Their daughter, Fianna Francis Masterson, is nine.

Phillips, who was in the 2000 film Almost Famous, notably stood by Masterson throughout his lengthy legal proceedings on rape charges.

Masterson, 47, was sentenced earlier in September in Los Angeles County to 30 years to life in prison after being convicted of two counts of rape.

He was found guilty in May, following a second trial that stemmed from accusations made by three women he met through the Church of Scientology.

Masterson waived his right to speak at his sentencing hearing. He had no visible reaction when it was handed down.

He maintains his innocence and his lawyers said they plan to appeal, contending there were problems with evidence and constitutional issues with his conviction.

Phillips was in court for his sentencing, and wept at one point.

“Danny is an amazing father. Our daughter and I are heartbroken that he is not home with us. It has been very difficult without him here,” she wrote in a letter to Judge Charlaine F. Olmedo.

“We need him more than you can imagine. I know he has been convicted of serious crimes. But the man I married has only been an extraordinary husband to me and a devoted father to our daughter.”

Elsewhere, Masterson’s former co-star Ashton Kutcher has stepped down from his anti-sex-trafficking organisation following outrage over letters he and wife Mila Kunis wrote asking for leniency in sentencing the actor.

Kutcher announced earlier this week he would resign effective immediately from his role as board chairman at Thorn, an organisation whose goal is to address the role the internet plays in child sex trafficking and abuse.

Kutcher founded the group with his then-wife, Demi Moore, in 2009.

“After my wife and I spent several days of listening, personal reflection, learning, and conversations with survivors and the employees and leadership at Thorn, I have determined the responsible thing for me to do is resign,” Kutcher wrote in a letter shared by Thorn.

“I cannot allow my error in judgment to distract from our efforts and the children we serve.”

Kutcher apologised to survivors of sexual assault for the letter he wrote that defended Masterson’s character.

Neither Kunis nor Kutcher argued that Masterson was not guilty, but they vouched for the person they knew him to be.

“The character statement I submitted is yet another painful instance of questioning victims who are brave enough to share their experiences,” Kutcher wrote.

“This is precisely what we have all worked to reverse over the last decade.”

Kunis, who was also a star on That ’70s Show, wrote another letter on Masterson’s behalf.

“From the very beginning, I could sense his innate goodness and genuine nature,” she wrote.

“His caring nature and ability to offer guidance have been instrumental in my growth both personally and professionally.”

In a video posted to Instagram, the couple clarified why they wrote the letters a day after they were publicised.

“They were written for the judge to read and not to undermine the testimony of the victims or retraumatise them in any way,” Kutcher said.

“We would never want to do that and we’re sorry if that has taken place.”

Kunis is also stepping down from her role as an observer on the Thorn board, according to a story in Time, which first reported the resignations.

“We would not be the Thorn that we are today without Ashton’s contributions,” the organisation said in a statement last week.

“He has played a significant role in the impact we have made, and we are grateful for his participation over the last 15 years.”

-with AAP