Senior Sergeant Patrick Carson, 39, pleaded not guilty to two counts of sexual intercourse without consent with the woman, then 19, in Darwin during 2020.

The Crown accused the married officer of exploiting his position as a father figure to take advantage of the young woman, who'd recently arrived in the Top End.

But the Supreme Court jury found him not guilty of both counts of rape after deliberating for 45 minutes on Wednesday.

Outside court, Sen Sgt Carson thanked his wife, family and friends "for their unwavering support across the past 21 months".

"There are no winners in a case like this. I look forward to putting this painful period behind us," he told reporters.

The eight-day trial, which was closed to the public for most of the proceedings, heard Sen Sgt Carson and the woman developed an intense relationship over several months after meeting at an exercise group.

Prosecutor Marty Aust described the woman as a shy teenager, who was lacking in confidence, socially inadequate and immature.

He said she had few friends and found it difficult to make "good decisions in stressful situations".

Sen Sgt Carson was accused of controlling aspects of the teen's life to enable him to take advantage of her in a sexual manner.

It allegedly led to the pair being alone at the home Sen Sgt Carson shared with his wife and children, where the officer was accused of raping the woman after the duo had massaged each other on his patio.

He was accused of a second attack about six weeks later, forcefully touching the woman on a couch at a mutual friend's home.

During the hearing, Sen Sgt Carson's lawyer, Mary Chalmers, told the jury that the evidence showed the woman had consented to the officer's sexual advances and conduct.

Ms Chalmers also said the woman had "painted a picture of a controlling and frightful man who lured her into a relationship" to investigators.

"Nearly everything she said about it turned out to be either a lie or a gross mis-characterisation or a twisting of reality to fit a narrative, her narrative of being raped," she said.

Australian Associated Press