A 19-year-old is facing life in prison for killing a man who allegedly raped her and sold her for sex after a judge ruled that she cannot use a Wisconsin law that shields sex trafficking victims as a defense.

Chrystul Kizer met Randy Volar in 2016 when she was 16 and he was 33. Authorities say she was one of about a dozen victims Volar sexually abused and filmed without their consent.

On the night of June 5, 2018, Chrystul shot Volar in the head twice at his home in Kenosha, Wisconsin, before setting his body on fire and fleeing the scene in his BMW.

Police located the vehicle hours later in Milwaukee and linked it to Chrystul, who confessed to killing him when questioned by police.

Four months earlier, Volar had been arrested on charges of child enticement, using a computer to facilitate a child sex crime, and second-degree sexual assault of a child. Photo and video evidence found at his home indicated that Chrystul was one of his victims.

Chrystul Kizer, 19, (left) is facing life in prison for killing 34-year-old Randy Volar (right), the man who allegedly raped her and sold her for sex

Chrystul confessed to shooting Volar in the head twice before burning his body at his home in Kenosha, Wisconsin, on June 5, 2018. Volar's charred home is pictured above

Volar was inexplicably released from jail the day after his arrest, without bail, and remained free until the night Chrystul shot him.

District Attorney Michael Graveley, whose office knew of the evidence against against Volar but held off on prosecuting him, charged Chrystul with first-degree intentional homicide and homicide.

The prosecutor has argued that Chrystal had pre-planned the murder, based on text messages she sent to friends and a selfie she posted on social media two hours before Volar's body was found, which captioned 'My Mugshot.'

Chrystul, now 19, has maintained that she did not go to Volar's home that night with the intent to kill him, and says she acted in self defense after he drugged her and tried to have sex with her.

The teen's lawyers sought to apply an 'affirmative defense' under a state law which allows victims of sex trafficking to be acquitted of certain charges if they can prove they committed the crime because they were being trafficked.

A judge ruled on December 9 that Wisconsin's affirmative defense did not apply to Chrystul's case.

Her lawyer is now preparing to appeal that ruling as Chrystul remains in jail.

Chrystul has maintained that she killed Volar in self defense after he drugged her and tried to have sex with her. The teen is seen in court in 2018

The Washington Post explored the complex inner-workings of the case in a lengthy feature published on Tuesday. The piece included nearly five hours of jail interviews with Chrystul.

The teen said she first met Volar after he responded to an ad she had posted on Backpage.com, a site that served as one of the country's largest marketplaces for prostitution before it was shut down last year for facilitating human trafficking.

Chrystul told Volar that she was 16, and soon began seeing him every other week. The Post describes how Volar groomed her by buying her expensive gifts and giving her money to bring home to her family.

The teen said Volar made it clear that he wanted to be repaid with sex.

'I told him that I never wanted to do that,' Chrystul said. 'He said that I had to owe him that.'

Chrystul said Volar also sold her through Backpage.com to other people, and would drive her to hotel rooms for meet-ups and then take the cash she earned.

As Volar became more demanding, Chrystul said she tried to distance herself from him. When she told him that she couldn't see him anymore because she was getting serious with her boyfriend, Delane Nelson, he got angry.

'He had started to talk violent and stuff,' she said. 'I was going to stop talking to him, and he said if I did that he was going to kill me.'

In May 2018, Chrystul’s boyfriend, Nelson, started to get suspicious that someone may be following her, so he gave her a .380 pistol and taught her how to use it.

The day before Volar's murder, Chrystul had a fight with Nelson. Fearing that he would physically hurt her, as he'd done in the past, Chrystul texted Volar and asked if she could come to his house. She brought the pistol with her.

'I had went into the house. … He had ordered some pizza. We were smoking, and he asked me if I wanted to drink any liquor,' Chrystul said.

'And then he had gave me this drug. I don't know what it's called. And after that, we started to watch movies. … And then, the drug, it made me feel weird or whatever.

'He started to touch my leg and then like I had jumped and tell him that I didn't want to do that. I just thought that I didn't want to do that stuff anymore because I was trying to change.

'I tried to get up, to get away from him but I had tripped, and I fell on the floor, and he had got on top of me.

'And he was trying to like, rip my pants off, my jeans that I had on. … I was, like, wiggling. Cause once me and [Nelson] had fought, he had tried to pin me down, but I'll wiggle to get loose.'

Chrystul said she doesn't remember retrieving the pistol, but she can still hear the noise it made when she pulled the trigger.

'Like a pop. A high pop,' she said.

She also said she didn't remember starting the fire, which neighbors reported to police after she fled the scene at around 5am.

Authorities linked Chrystul to the crime after finding Volar's missing BMW in Milwaukee and connecting items inside the car to her and her brother.

Chrystul said she met Volar in 2016 after he responded to an ad she had posted on Backpage.com, a site that served as one of the country's largest marketplaces for prostitution before it was shut down last year for facilitating human trafficking

Chrystul's story changed several times over the course of her first interview with investigators.

She initially claimed that she didn't know Volar, and then said she saw a woman shoot him. Finally, she confessed that she was the one who killed him because she 'got upset and was tired of Volar touching her'.

Her claims of abuse were already well supported by the cache of evidence police had collected in their investigation of Volar, which was sparked in February 2018 after a different teenage girl reported that he had been paying her for sex and filming it.

Volar was arrested in February 2018 for charges including child sexual assault. He was inexplicably released without bail and remained free until his murder

When police searched his home, they found computers and other electronics with videos and photos of him having sex with girls who appeared to be as young as 12. They also came across a bank account with $1.5million in transfers, activity consistent with sex trafficking.

The district attorney's office allegedly tried to withhold the evidence against Volar from Chrystul's defense team, arguing that they didn't have the right to review the case file.

When they were finally granted access to the evidence, Chrystul's lawyers began building their 'affirmative' defense.

The defense is based on a statute recognized in many states, including Wisconsin, which allows sex-trafficking victims to use the fact that they were trafficked as a defense against certain charges.

Wisconsin's version of the law is broad and doesn't specify which crimes the defense can be used for. It has never been used in cases involving homicide or other violent crimes, the Post reported.

Prosecutors argued that the affirmative defense did not apply because Volar's murder was premeditated.

If the judge had ruled that the affirmative defense did apply, a jury would have been tasked with deciding whether her crimes were a 'direct result' of being trafficked.

However, Judge David P Wilk announced at a hearing earlier this month that the defense is 'limited', and did not fit Chrystul's case.

In his ruling, Wilk said that allowing the teen to use it would set an extremely dangerous precedent for other cases involving trafficking victims accused of violent crimes.

'The court is satisfied that a blanket affirmative defense to all acts leads to an absurd result,' Wilk said.

Chrystul was subsequently returned to jail to await her trial, where she faces up to life in prison, the mandatory minimum sentence for intentional homicide.

Her lawyer has said he intends to appeal the ruling.

Chrystul's case garnered attention due to its striking similarities to that of Cyntoia Brown.

Brown was granted clemency in August after serving 15 years in prison for murdering the man who bought her for sex when she was underage, following a massive social media campaign in which celebrities including Kim Kardashian and Rihanna advocated for her release.