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A surveillance camera has captured a hammer-wielding killer standing outside a school bathroom moments before he bludgeoned his ex-girlfriend to death.
The chilling image shows hockey coach Paul Thijssen looking directly at a CCTV camera outside the gym bathroom at the elite St Andrew's Cathedral School in Sydney on October 25, 2023.
Moments later, he charged into the bathroom with a hammer in his hand and struck water polo coach Lilie James more than 25 times in the head and neck.
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Footage released by the NSW Coroners Court today shows Thijssen practising the murder outside the bathroom earlier in the day.
The 24-year-old can be seen alternating the hammer between his hands as he lunges forward and pushes open the bathroom door in what was described at the inquest as a "dry run" for the killing.
Thijssen had earlier blocked off one of the bathrooms so the 21-year-old would be forced to use the disabled bathroom.
Another video released by the court shows Thijssen testing the weight of hammers as he browses at a Mitre 10 hardware store.
He walks away with a hammer in hand, but an inquest into James' death heard it was not the hammer used to beat his ex-girlfriend to death.
James ended their casual two-month relationship five days before she was killed in the bathroom.
Domestic violence expert Anna Butler previously told the inquest that patterns of coercive control were evident throughout their short relationship.
When James had previously tried to break up with Thijssen, he used abusive, derogatory and gaslighting language to negate her autonomy.
He escalated his emotionally abusive behaviour when he shared an intimate image of the 21-year-old with friends and stalked her after she expressed doubts about their relationship.
Thijssen felt growing anger and resentment that he no longer controlled their status so he used a cache of well-honed manipulative tactics to try to regain his control, Butler said.
Forensic psychologist Katie Seidler noted he had no history of aggression and there was probably nothing that could have been done to prevent the gender-based violence.
Although the 24-year-old wielded coercive control in his relationships, she found there were no obvious warning signs or indicators of violence to predict the tragic outcome.
Dr Seidler theorised Thijssen killed James because he was terrified the break-up would unravel his facade of perfection.
He had a fragile sense of self and saw himself as inadequate and unworthy, which led him to lie to create a flawless public image, the expert said.
Issues of coercive control and unacceptable behaviour in relationships are being examined by the inquest into the deaths of James and Thijssen, who died hours after his ex-girlfriend.
Coroner Teresa O'Sullivan is assessing whether his death was self-inflicted.
The inquest will also hear statements from James' family as it draws to a close.
Support is available from the National Sexual Assault, Domestic and Family Violence Counselling Service at 1800RESPECT (1800 737 732).
