A former New York City police chief embroiled in an overtime-abuse investigation ordered the removal of tracking devices from department vehicles assigned to him and his subordinates, according to two people with knowledge of the matter.

The devices, known as automated vehicle location devices, are used to keep officers safe and can help record their time and movements for purposes of accountability.

The former police official, Jeffrey Maddrey, who resigned as chief of department in December, asked during his two-year tenure in that role that the devices be taken off the vehicles, according to the people, who spoke on condition of anonymity because of the investigation’s confidentiality. It was unclear how many vehicles were involved.

Mr. Maddrey, whose home was searched by federal agents in January, was the department’s highest-ranking uniformed officer, a job from which he oversaw operational planning and the development of crime-fighting strategies. During his tenure, which began in December 2022, overtime use exploded, particularly by officers who worked for him and other high-ranking officials with close ties to Mayor Eric Adams.

Mr. Maddrey, once a close ally of Mr. Adams, resigned in December after he was accused of pressuring a lieutenant who worked in his office into a sexual relationship in exchange for giving her overtime opportunities. This week, four former chiefs filed lawsuits against Mr. Adams and Mr. Maddrey, among other officials, accusing them of creating a culture of cronyism and corruption, where officers who tried to resist faced humiliation and retaliation.

Federal investigators learned of the removal of the tracking devices as they examined allegations of overtime abuse and misconduct against Mr. Maddrey, which began after the sexual abuse accusation surfaced in December. Federal prosecutors from the Southern District of New York have questioned or have sent subpoenas to detectives, officers and high-ranking department officials, according to one of the people who was familiar with the investigation. Several officers received subpoenas in the past month, according to the person.