Murder of Aaron Pajich

On 13 June 2016, 18-year-old Aaron Lee Pajich-Sweetman, who had autism spectrum disorder, disappeared from Rockingham, Western Australia. He had been driven that morning by his landlady from the house where he was lodging in Waikiki to Rockingham Centre, and was reported missing two days later after failing to return home. Investigators found that the last answered call to his mobile phone had come from the phone of Trudi Lenon, and CCTV footage from Rockingham Centre showed Lenon driving out of the carpark with Jemma Lilley and Pajich inside her car. Footage from a camera outside the house shared by Lilley and Lenon in Orelia also showed Pajich entering the property with the two women later that morning.

On the night of 20 June 2016, police searched the Orelia property and, after digging up concrete tiles in the backyard, found Pajich's body buried in a shallow grave approximately 30 centimetres deep. A post-mortem examination found he had suffered stab wounds to his neck and chest that severed a jugular vein and punctured his liver and lungs, along with marks on his neck consistent with strangulation by a garrote and defensive wounds on his hands.

Lilley, then 25, and Lenon, then 42, were arrested and charged with murder on 22 June 2016. Both pleaded not guilty at Stirling Gardens Magistrates Court on 26 October 2016. Their trial began on 2 October 2017 in the Supreme Court of Western Australia. The prosecution alleged that Lenon telephoned Pajich on the morning of 13 June 2016 to invite him to the house, and that Lilley choked him with a garrote before stabbing him while Lenon helped pin him down. A co-worker of Lilley's testified that she told him, five days after Pajich disappeared, that she and Lenon had killed him. Lenon told police she witnessed Lilley choking and stabbing Pajich and admitted helping to hide evidence, while Lilley denied involvement, saying she had last seen Pajich in the living room before falling asleep. Lists of torture methods and related items found in the house were said by the defendants to relate to books they were writing.

On 1 November 2017, following a two-hour jury deliberation, both women were convicted of the murder of Pajich. On 28 February 2018, Justice Stephen Hall sentenced them to life imprisonment with a minimum term of 28 years, describing the killing as "morally repugnant" and stating it was committed for the women's "own pleasure." Lilley's appeal against her conviction, lodged on 10 April 2019, was rejected on 22 October 2019.

Following the conviction, Lenon was seriously injured in prison on 1 January 2018 when a fellow inmate poured boiling water on her, causing burns to 21% of her body; the inmate was sentenced to five years for causing bodily harm.