EVERETT — A 19-year-old woman who cut her boyfriend’s trachea with the knife he gave her for Christmas last year has been spared a lengthy prison sentence.

Jurors on Friday convicted Tiana Star-Cox of second-degree assault with a deadly weapon. After a few hours of deliberations they couldn’t reach an agreement on the more serious charge of first-degree assault. That conviction could have sent Star Cox to prison for up to a decade.

Star-Cox had served about eight months in jail before she posted bail. She doesn’t face much more time behind bars.

Snohomish County Superior Court Judge Richard Okrent allowed the defendant to remain free pending her sentencing next month.

There’s a “greater risk of her not showing up if we take her away from her family,” Okrent said.

Star-Cox claimed that she was defending herself against an abusive boyfriend during an argument over booze. She slashed the man’s throat and stabbed him in the chest.

Jurors were told that Star-Cox was trapped in a violent relationship with a convicted felon who thrived on threatening people. Her lawyers said she had a right to defend herself.

“She did not have to wait to let (him) hurt her,” defense attorney Kelly Canary said Friday.

The defense put their client’s ex-boyfriend on trial. They also criticized Everett Police Department’s investigation, saying detectives didn’t do enough to explore Star-Cox’s claims that she was a battered woman.

Snohomish County deputy prosecutor Tobin Darrow defended the police investigation, saying detectives focused on what actually happened on Dec. 26, 2013.

Darrow called Star-Cox’s story plastic.

“It bends any way it needs to,” he said.

There is no question that the victim is obnoxious and controlling, Darrow said.

“Being obnoxious was not a reason to slit his throat,” he said.

Jurors were told that the couple had spent the day fishing in Gold Bar. The man purchased a bottle of Fireball whiskey and they later drove to Whidbey Island, looking for a place to have sex. Before heading home they stopped by the Everett Market so the man could buy a beer.

Star-Cox said the man was upset that she hadn’t been drinking enough of the whiskey.

He testified that he was attacked out of nowhere.

Star-Cox said he grabbed her by the hair and wouldn’t let her get out of the car. She said there was a struggle over her knife. Star-Cox was afraid for her life, jurors were told.

“She doesn’t want to attack him. This is the man she loves. Why? I have no idea,” Canary said.

The truth, Darrow said, lies in the man’s injuries. He was slashed in the throat and stabbed in the chest. That doesn’t happen during a struggle. That happens if a person is ambushed, the deputy prosecutor said.

The defendant was out to teach the man a lesson. She was fed up with the way he talked to her and the names he called her, Darrow said.

“You don’t get to slash someone’s throat and stab them in the chest because they pull your hair,” he said.

Diana Hefley: 425-339-3463; hefley@heraldnet.com. Twitter: @dianahefley