Bill Cosby sentenced to at least 3 years in prison for sexual assault

Bill Cosby has been sentenced to at least three years behind bars for sexual assault.

In April, the 81-year-old comedian was found guilty on three counts of aggravated indecent assault for drugging and sexually assaulting his one-time friend Andrea Constand.

On Wednesday morning (NZ time), Judge Steven O'Neill said Cosby is a "sexually violent predator" who would serve between three and 10 years behind bars.

"I'm not permitted to treat him any differently based on who he is or who he was," O'Neill said.

Cosby will face "total confinement" and will be placed on the sex offender's registry.

Ms Constand read a powerful victim impact statement, saying Cosby had "crushed" her spirit.

"After the assault, I wasn't sure what had actually happened but the pain spoke volumes," she said.

"The shame was overwhelming. Self-doubt and confusion kept me from turning to my family or friends as I normally did. I felt completely alone, unable to trust anyone, including myself."

O'Neill also fined Cosby US$25,000 and ordered him to pay the costs of the prosecution, calling Cosby's crime "very serious".

There was no visible reaction from the disgraced entertainer.