Police use wife's fitness tracker as evidence to charge husband

Police have used readings from the fitness tracker a woman was wearing when she was killed as evidence to charge her husband with murder, in what may be a world first.

Richard Dabate claimed his wife, Connie was killed by a masked intruder in their Connecticut home on Dec 23, 2015, NY Daily News reports.

He called 911 and told the emergency worker the couple had been attacked by a "tall, obese man" wearing "camouflage and a mask" who had shot his wife, and tied him up before he had managed to escape by burning the burglar with a torch.

Police found Dabate still tied to the chair when they entered the house, but realised something else was amiss when they tried to corroborate his version of events with his wife's tracker.

The device was still tracking her heart rate and steps an hour after he had claimed she had been shot.

Detectives then checked the pair's phone records and found conversations between Mr Dabate and his wife where he had demanded a divorce a year prior to the murder.

There was also a series of texts from his reported pregnant mistress, including one which read: "I'm ready for u big boy". Along with credit card bills for flowers and hotels.

Dabate was arrested and now faces charges of murder, tampering with evidence and making a false statement.

He has pleaded not guilty to all charges and is currently out of custody on a $1m bail bond. He's scheduled to return to court on Friday.