A case of mistaken identity led a 46-year-old man to believe a young woman consented to having sex with him following a night of drinking, a defence lawyer told B.C. Supreme Court.

A 12-person jury remained sequestered Friday in the sexual assault trial of Kenneth Tomma.

Tomma is charged with sexual assault and break and enter with intent after an incident in the early morning hours of Oct. 23, 2010. Lawyers concluded final arguments Friday morning, leaving it to the jury to decide on Tomma's guilt or innocence.

"At the end of the day, it's mistaken identity," defence lawyer Sheldon Tate told the jury comprised of seven women and five men.

A group of young Shuswap resort employees and a few neighbours, including Tomma, had a party that night finishing around midnight, when all went to bed. Tomma testified he later left his apartment to bum a cigarette.

He unsuccessfully tried the doors of several of his young friends, but all were locked. Tomma then knocked on the woman's door and went inside after hearing a noise.

Soon after he was having sex with her.

Tate noted in her first statement to RCMP, in the haze of alchohol and sleep, the woman said realized she was having sexual intercourse, "went with it" and was "giving back."

Tate said what she didn't know, however, was the man who crawled into her bed was not another, much younger man to whom she was attracted. Instead, it was Tomma, a neighbour she knew only as an acquaintance.

Tate said when she finally realized her error — shocked and embarrassed — she ran next door to her friends' apartment. She never used the words rape or sexual assault.

Her friends called police and confronted Tomma, assuming it was a sexual assault and putting into gear the machinery of police, doctors and an eventual sexual assault examination.

Over the next months and years she rearranged her story to clear her own mind of an embarrassing mistake, Tate said in his submission.

It was clear from five days of testimony that Tomma was never violent nor forcibly held the young woman.

In his submission to the jury, Crown lawyer Joel Gold said Tomma failed to take steps to ensure the woman consented to sex.

"Being silent is not the same as saying 'yes.' She was unconscious or barely conscious. . . . She was at great disadvantage, something he took advantage of."

Both the woman and Tomma testified to being drunk that night. Tomma repeatedly told police after he was arrested, "I'm sorry, I'm sorry — I got too drunk."

But Tate said that admission only shows Tomma felt bad about her response.

"We're dealing with somebody — Mr. Tomma — who is not a particularly sophisticated individual. He's a First Nations survivor of a residential school. He's suffered a brain injury. . . . There's clearly a way of speaking that's not the Queen's English."

That unsophistication along with the effects of alcohol caused him to make a bold move with the woman. He knocked and entered her room, after hearing a muffled response.

"He's thinking what happened is the normal course after a party. . . . Because of his attraction, he makes what we call 'the move.'

"If I touch someone on the shoulder and they respond, things go to the next stage. . . . What we see is a natural and normal progression from foreplay to sexual intercourse."

The jury will continue its deliberations through the weekend if necessary.