Digital evidence extracted from Lindsay Clancy's Apple Watch and iPhone provided prosecutors with a minute-by-minute account of her movements in the hours leading up to the deaths of her three young children. The data, presented on the 14th day of her trial, tracked her heart rate and activity within her Duxbury home on January 2023.
Ian Whiffin, a digital-forensics expert with Cellebrite, testified that the devices recorded Clancy's heart rate and movement until approximately 5:38 p.m. Her Apple Watch logged a final heart-rate measurement of 57 beats per minute at 5:23:52 p.m. Whiffin stated that the device could have stopped collecting data if it was removed, turned off, or ran out of battery. The iPhone continued to record activity, detecting movement up one flight of stairs around 5:33 p.m. and a second flight approximately five minutes later.
During this period, her husband, Patrick Clancy, called her phone, and a 14-second return call was placed from the locked iPhone. While an exact timestamp for the children's strangulation has not been definitively established, trial evidence and phone records suggest the killings occurred between approximately 5:34 p.m. and 6:09 p.m. while her husband was out of the house.
Whiffin, who has analyzed over 1,000 phones and testified extensively in court, explained how Apple Health data, collected by iPhones and paired devices like the Apple Watch, can store metrics such as heart rate, steps, and flights climbed. The stair activity was registered when the phone detected movement and an elevation increase of about 10 feet. Whiffin acknowledged that the data tracked the devices, not necessarily the person carrying them, and that errors or duplicate entries could occur, though rare.
The defense attorney challenged the extent to which the digital evidence could establish Clancy's actions, noting that the devices might have been put down or stopped recording while she continued to move. Whiffin conceded that it was unknown what Clancy was doing after 5:38 p.m., when the data effectively became a "blackout."
Earlier activity recorded by the phone included plotting a route via Apple Maps at 4:13 p.m. and a search for Pedia-Lax liquid stool softener on Safari an hour later. A text message with the same content was sent to Patrick Clancy around 5:15 p.m., shortly after the phone was unlocked and then locked again. The phone was not unlocked again until the outgoing call to Patrick was placed from the lock screen. In the weeks preceding the children's deaths, internet searches recovered from the phone included queries about Wellbutrin, ketamine for suicidal ideation, and symptoms of postpartum psychosis.
IMAGE2 Lindsay Clancy is accused of strangling her three children in their Duxbury home in January 2023. She has pleaded not guilty, claiming she was suffering from postpartum psychosis.