The jury at Kalen Schlatter's first-degree murder trial in the death of Toronto woman Tess Richey never heard about his "obsessive" interest in violent pornography that featured non-consensual sex and images of choking.

The jury also didn't hear about Schlatter's interest in choking his previous sexual partners. Those revelations are contained in a pre-trial ruling from Superior Court Justice Michael Dambrot, who ordered that evidence be excluded from the trial.

The Crown alleges Schlatter sexually assaulted and then strangled Richey before leaving her body at the bottom of an outdoor stairwell in the city's gay village in 2017.

He has pleaded not guilty to first-degree murder. These details were covered as part of a publication ban that has dropped now that jurors are deliberating on a verdict.

In his ruling, Dambrot said the "probative value of the evidence is apparent.

"Evidence that the accused engages in sex that includes choking his sexual partner, albeit consensually, taken together with his obsessive interest in violent pornography that also includes non-consensual 'choke-out' sex, tends to show a propensity on his part to engage in violent sex involving choking."

According to court documents, Google searches extracted from Schlatter's cellphone included searches for several "forced" sexual acts. Investigators also found the phone had been used to access a pornographic video titled "Teen Forced and then Thrown Away Like Garbage," which depicts a violent sexual assault including neck compression.

Richey, 22, went missing on Nov. 25, 2017 after a night out with a high school friend. Her body was found four days later. (Tess Richey/Facebook)

Court documents also include information provided by two of Schlatter's past sexual partners, which included details about Schlatter engaging in sex involving choking.

The ruling outlines instances where Schlatter had sex with the two women, sometimes in a threesome. They are referred to as A.B. and C.D. in the court documents. They met in 2017.

"Throughout the summer, the group had numerous social contacts," the court documents read.

"If they went drinking or to a club, the accused, A.B. and C.D. would engage in sex the following morning, usually as a threesome. On some of these occasions, A.B. said that the accused had choked her. Before he did, they pre-negotiated the choking," the ruling reads. "They also discussed how A.B. could tell Mr. Schlatter to stop," which included tapping the side of the bed.

The ruling says that when she tapped the side of the bed or his leg, Schlatter stopped immediately.

"When he did it, it seemed to make him more sexually stimulated, and more ready to engage in further sexual activity," the court documents read.

In the end, Dambrot ruled this evidence could only be included at the trial if the defence chose to "attack the integrity of the police investigation, or argue that the police exhibited tunnel vision in focusing on the accused murderer. Admissible or not, this evidence is highly significant in explaining and informing the investigative decisions made by the police in the case."

adam.carter@cbc.ca