Biomechanics expert says mower could not have been on Frances Crawford when she hit wall
Professor David Ackland testified that it was very unlikely a ride-on mower could have ended up on Frances Crawford’s body at the bottom of a retaining wall, challenging the prosecution’s accident theory.
Former Royal Australian Air Force pilot Robert Crawford, 49, has pleaded not guilty to the July 2024 death of his wife Frances at their rural Queensland property. The defence maintains the incident was an accidental mower rollover, while the prosecution argues the death was staged.
During the trial, Crown prosecutor Chris Cook questioned biomechanics professor David Ackland about the plausibility of Frances’ head striking a rock and her body ending up 1.8 metres from the retaining wall. Ackland responded, “In my opinion, no,” adding that simulations could not reproduce the body’s position without a projectile-like motion.
Ackland explained that for the body to travel that distance, the mower would need to be moving at maximum speed (about 2.4 m/s) with no impact to the rock, a scenario he described as “very unlikely.” He emphasized that his analysis focused on the body’s final resting place rather than the mower’s position.
The trial also revealed Crawford’s history of extramarital relationships and communications with a buyer’s agent, Rebecca Lawler, after separating from Frances in 2023. Text messages exchanged between them were presented as evidence of his personal conduct.
Justice Lincoln Crowley’s proceedings continue, with further testimony expected on the circumstances surrounding Frances Crawford’s death.