A Greek helicopter pilot told police that armed intruders had broken into his home, tied him up and murdered his wife. His own digital trail, combined with data from his wife's smartwatch, helped investigators reconstruct what happened.
On the morning of 11 May 2021, Charalambos 'Babis' Anagnostopoulos called Greek police from the couple's home in Glyka Nera, a suburb of Athens.
Officers arrived to find Anagnostopoulos bound and his 20-year-old wife, Caroline Crouch, dead in the bedroom. Their 11-month-old daughter was at the scene, while the family's dog, Roxy, had also been killed.
Anagnostopoulos had claimed that several armed burglars had entered the house, demanded money and attacked the family. He said the intruders had tied him up and killed Caroline. For weeks, investigators treated the apparent burglary as a murder committed by unknown attackers.
But the digital evidence began to undermine the story.
The Smartwatch Recorded Caroline's Final Minutes
The most striking evidence came from Caroline's biometric smartwatch. According to forensic findings reported during the investigation, the device recorded her heart rate while she was asleep and then showed a sharp increase at about 4:05 a.m. Her heart-rate readings stopped at approximately 4:11 a.m.
Greek forensic reporting said the data was consistent with Caroline being asleep before the sharp change and with the fatal attack taking place between approximately 4:05 and 4:11 a.m.
The watch did not identify the person responsible for her death. Its importance was more specific: it provided investigators with a physiological timeline that could be compared against Anagnostopoulos's account of an attack by intruders.
The digital record became particularly significant when combined with data from other devices.
His Own Phone Helped Contradict His Story
Investigators also examined activity data from Anagnostopoulos's phone, including the Fitbit fitness application installed on the device. That data showed movement during periods when Anagnostopoulos claimed he had been restrained and unable to move freely.
The investigation also reconstructed activity around the couple's home using phone and security-camera records. The digital evidence showed that Anagnostopoulos had been active inside the house hours before the time he claimed the burglars arrived.
That was difficult to reconcile with his account of being helplessly tied up while strangers moved through the property.
The combination of data from Caroline's smartwatch, Anagnostopoulos's phone and the home's security system became part of the prosecution's broader reconstruction of the night.
Anagnostopoulos had removed the camera and its memory card, apparently attempting to eliminate evidence of what happened inside the house. But investigators were able to examine server and device records associated with the camera.
The Timeline Before Caroline's Death
Investigators examined communications between the couple shortly before the killing.
Reports from the investigation said Caroline had sent messages to Anagnostopoulos late on 10 May, including one at about 11:18 p.m. and another around 11:42 p.m. The messages reflected an argument and Caroline's desire to leave the relationship.
Activity recorded on Anagnostopoulos's phone subsequently showed movement around the house.
The prosecution used the sequence to argue that the killing was not simply an impulsive act but followed a period in which Anagnostopoulos had been considering his actions.
The defence, however, argued that the murder was committed in the heat of an argument rather than being premeditated.
Police Realised the Burglary Story Was False
Investigators found other inconsistencies in Anagnostopoulos's account besides the smartwatch data and found no convincing evidence that the home had been attacked by the group of burglars he described.
He had claimed that intruders entered the property, restrained him and killed Caroline before fleeing. He maintained the burglary story for almost six weeks.
In June 2021, police took him from a memorial gathering for Caroline to Athens for further questioning after investigators said they had obtained new evidence. During prolonged questioning, he eventually confessed to killing his wife and staging the burglary.
Reuters reported at the time that CCTV evidence and the smartwatch data had helped undermine his account before his confession.
The Court Found Him Guilty of Premeditated Murder
Anagnostopoulos went on trial in Athens in 2022. The prosecution argued that the evidence showed planning and deliberate action. The defence sought to portray the killing as the result of an argument that had spiralled out of control.
On 16 May 2022, a seven-member mixed court unanimously found Anagnostopoulos guilty of the premeditated murder of Caroline, the killing of the family dog and offences connected with misleading authorities. He received a life sentence for Caroline's murder.
He was also sentenced to additional imprisonment for killing the dog and for misleading investigators. Contemporary reports put the additional sentence at 11 years and six months in total, alongside a fine.
The court rejected his attempt to obtain mitigating treatment for the murder.
The Conviction Was Later Upheld
Anagnostopoulos appealed the conviction and sentence.
In September 2023, the Athens Mixed Jury Court of Appeal upheld the life sentence. It also upheld additional punishment of 11 years and six months and a €21,000 ($24,229) fine for the other offences.
In June 2023, before the appeal proceedings concluded, Anagnostopoulos announced that he would withdraw his appeal. The decision meant the original life sentence would remain in place.
The case has received renewed attention in 2026 through Amazon's Prime Video documentary The Fitbit Killer.
Prime Video describes the two-part documentary as examining Caroline's murder, the apparent robbery and the evidence that challenged the original account, including Caroline's diary and smartwatch data. The episodes were released in August in some markets, while Amazon's UK schedule lists the title for 15 September.
The documentary's title reflects the role wearable technology played in the investigation.
