On an unseasonably warm morning in February 2017, a 75-year-old white motorist was making his way north on Interstate 95 in Westbrook, Conn., when he was pulled over by a state trooper and charged with a traffic violation.

That is, at least, according to a traffic stop report filed by the officer. But no ticket appears to have been issued.

In fact, there may not have been any stop. The driver may not even exist.

State officials believe that the trooper was among more than 100 Connecticut state police officers who may have filed false reports of traffic stops in recent years, possibly to boost the internal statistics used to measure their performance.

A recent audit described “a pattern of record manipulation” and said there was a “high likelihood” that at least 25,966 recorded stops between 2014 and 2021 were false and that as many as 58,553 may have been, at minimum, inaccurate.

“What was the motivation here, really?” asked Ken Barone, a co-author of the audit. Most likely, he said, “the motivation here was to appear productive.”

The idea that Connecticut’s state police officers may have conducted a yearslong scheme of systematic deceit has shocked the public, embarrassed the state’s law enforcement community and enraged its political leadership at a time of national conversations about police accountability.

The U.S. Department of Justice is investigating, state officials said. Gov. Ned Lamont, a Democrat, has launched a separate inquiry.

“The trust and the confidence in Connecticut state police is clearly shaken by this,” said State Representative Steve Stafstrom, a Democrat and the co-chairman of the state legislature’s judiciary committee.

The ticket reports under scrutiny may have also irrevocably tainted the racial data that the state collects on traffic stops. That is because the motorists who were purportedly stopped were disproportionately white, said Mr. Barone, who is the manager of the Connecticut Racial Profiling Prohibition Project, which seeks to identify and address racial and ethnic disparities in traffic enforcement.

The auditors compiled their research by comparing two sets of data: court records of real tickets issued to real people and internal data from the state police.

“Every time Trooper A said they stopped a car and issued a ticket, I should be able to find said ticket in the court system,” Mr. Barone said.

But the numbers did not add up. Mr. Barone and his team kept finding reported tickets that had no match in the court system — no matter how they tried to account for typos or other mistakes. He said they had used an “extremely conservative” approach.

“The philosophy that we had was: ‘When in doubt, give them credit,’” he said.

But Mr. Barone said he saw almost no way that troopers could have made some of the stops they reported.

In one case, a trooper logged five registration violations over a 30-minute period. Another trooper reported issuing five speeding tickets in 22 minutes. Another reported three speeding tickets in 14 minutes. Still another claimed to have issued three wrong-lane tickets, in a work zone, in nine minutes.

Mr. Barone said that members of the Connecticut Racial Profiling Prohibition Project were inspired to begin the audit last summer after Hearst Connecticut Media reported that four troopers were found to have falsified records in 2018. They strongly suspected a much broader pattern, he said.

Now the auditors, who included researchers from the University of Connecticut and Northeastern University, say they believe the problem is widespread.

Their report, released earlier this summer, found 130 former and current officers who had filed suspicious reports. James C. Rovella, the head of the state’s Department of Emergency Services and Public Protection, told lawmakers in July that 68 of those officers were still active. He did not respond to a request for comment.

Some troopers have been cleared of wrongdoing in the weeks since the audit was released.

Andrew Matthews, the general counsel and executive director of the state police union, put that number at 27; Mr. Barone said the auditors had cleared only 20, because of duplicate badge numbers. The state police declined to comment, citing an ongoing investigation.

Experts in criminal justice say the ticket scandal has revealed a lack of accountability within the state police.

“If we can’t trust them for traffic tickets, how are we going to trust them for cases like sexual assault, or murder?” said Nicole Gonzalez Van Cleve, a sociologist at Brown University who studies policing and prosecutors.

“The state troopers sort of view themselves as better than local police officers,” said Mike Lawlor, a criminal justice professor at the University of New Haven, who is also a member of the state’s Police Officer Standards and Training Council, which certifies officers. “But also, over time, they’ve had a culture where there was essentially no real oversight of them.”

The state police union has sued to block the release of the names of the troopers under suspicion until the investigations conclude. Mr. Matthews said they are entitled to due process — and that revealing their identities could put them in danger.

He also cast doubt on the audit’s methodology: He said auditors had not done enough research to understand how the ticket reporting system works.

Although some state troopers had cruisers equipped with electronic ticket recording systems during the period of the audit, others had to write out tickets by hand. Mr. Matthews said that auditors had not appropriately checked electronic court records against the carbon copies of handwritten tickets on file with the state police.

“Why is everyone in such a rush to tarnish the good names of people that did nothing wrong?” he asked.

Mr. Matthews, a former state trooper, was among those whose reports were flagged. He denied any wrongdoing and said one of his cruisers did not have an electronic recording system.

“I did my job with the utmost integrity,” he said.

Instead of widespread dishonesty, Mr. Matthews suggested that there could have been data entry issues.

Maybe, he said, some of the stops resulted in infractions more serious than a ticket, and an officer misreported them as tickets. Perhaps a trooper issued a warning, instead of a ticket, but a dispatcher entered it incorrectly.

Advocates and lawyers said that they need accurate traffic stop data in part to assess whether officers are unfairly targeting Black and Hispanic drivers.

Connecticut outlawed racial profiling of drivers in 1999. The Racial Profiling Prohibition Project has been collecting and analyzing statewide data since 2013.

But the state troopers’ data is now “obsolete,” said Claudine Constant, the public policy and advocacy director for the American Civil Liberties Union of Connecticut.

In fact, the audit found that the reports under suspicion were almost 10 percentage points more likely than verified reports to involve white drivers, and about 4.5 percentage points less likely to involve Black or Hispanic drivers.

“This audit reveals a pretty breathtaking disrespect for the states’ racial prohibition law,” Ms. Constant said. “And even worse, the goal of attempting to reduce traffic stops that might be grounded in racism.”

Now, officials are trying to determine whether there was systematic fraud — and, if so, how high up it went.

“If they misused the system intentionally, the question that stems from that is: ‘Why was nobody arrested?’” said State Representative Craig Fishbein, a Republican who is the ranking House member of the legislature’s judiciary committee.

The scandal may also have repercussions across the justice system.

Already, the lawyer for a man accused of murder is arguing that he should be told whether the state police officers involved in the case were flagged in the audit — which would undermine their credibility. Mr. Lawlor, the criminal justice professor, said he expected other defense attorneys across the state to make similar arguments — until the names of troopers under investigation are released.