Two men accused of gang raping a teenage girl in Calgary have been found not guilty of sexual assault after the judge believed the testimony of the accused that the victim wanted rough sex.

Although he was acquitted of sexual assault, Adham El-Sakaan, 21, was convicted of sexual assault with a weapon for inserting an electric toothbrush into the victim without her consent.

Timothy Fanning, 21, El-Sakaan, and a third, underage friend had sex with a 17-year-old in December 2016 in the basement of the youngest boy's home. The girl's name is protected by a publication ban. CBC News is calling her Sara.

The youngest male admitted to raping Sara and pleaded guilty to sexual assault in 2017. The boy cannot be named under the Youth Criminal Justice Act because he's under 18. He cannot appeal on the basis of this new decision.

Fanning was escorted out of the courtroom by defence lawyer Balfour Der after being acquitted of both charges.

Justice Scott Brooker will hear sentencing submissions in July in Calgary from El-Sakaan's lawyer Joan Blumer and prosecutor Pam McCluskey.

Brooker said on Wednesday that he believed the testimony of the two young men who told the court the sex was consensual, and that Sara had asked for it to be rough.

A video was taken showing the teenage boys punching and slapping Sara while calling her a "slut" and a "bitch" and telling her to "shut the f--k up" while taking turns with her sexually.

They also laugh and egg each other on.

Brooker said he did not find the victim to be a credible witness because of "too many contradictions in her evidence."

Sara initially told authorities that she was forced to give oral sex to Fanning later in the night but changed her story and admitted she'd consented.

The judge found Sara changed part of her story and left out pieces when she initially reported the assault to police.

Earlier in the night, before any of the sexual activity, Sara texted a friend saying she was considering having sex with the three teens.

'Tailoring her evidence'

Those messages were deleted before she went to police. She explained it was because she was embarrassed, scared and worried police wouldn't believe her, but Brooker found she was "already tailoring her evidence of what happened."

Although Brooker said Fanning and El-Sakaan were "by no means stellar witnesses," having been "less than forthright" and even lied to police, the judge said he believed their testimony over the victim's.

Fanning and El-Sakaan both said Sara took off all her clothes, danced around, winked at them and then displayed what the judge described as "clear, unequivocal communication" of consent by inviting them to have sex with her.

No 'scintilla' of consent

The 2017 sentencing decision of the underage teen who pleaded guilty to sexual assaulting Sara provides another analysis of the video by a different judge.

Provincial Court Judge Richard O'Gorman wrote that the videos depicted "the most appalling acts of human depravity I have had the displeasure to witness as a judge."

"There is not one part of either video that shows any scintilla of consent," O'Gorman wrote.

"The victim is assaulted, yelled at, demeaned, insulted, manhandled like a rag doll, called a bitch and a whore several times, and viciously slapped on the face, breasts and buttock. She is visibly shaken and frightened; to suggest otherwise is simply ignorant."