Overview
- CCTV captured a woman delivering flowers to Hartley’s Helmshore home days before the killing in a reconnaissance to confirm she would answer the door.
- On January 14, 2016, Sarah Williams used a stun gun at the doorstep and stabbed Hartley 41 times, leaving her dead in the hallway.
- Williams and accomplice Katrina Walsh spent about 17 months planning the attack, tracking Ian Johnston, buying a stun gun in Germany and arranging a getaway car.
- Police arrested Williams three days later after forensic blood evidence was found in the vehicle and at her home, with Walsh’s diary entries detailing the plans.
- Both women were convicted of murder and sentenced to life—30 years minimum for Williams and 25 for Walsh—as officials denounced the crime as cold‑blooded and premeditated.