The Los Angeles Police Department fudged violent crime stats under the watch of Bill Bratton — cooking the books to keep down the number of serious assaults, a report said Thursday.

An estimated 14,000 cases from 2005 to 2012 were altered, leading people to believe the city’s crime rate was lower than it actually was, according to a Los Angeles Times analysis.

Before his tenure began as NYPD commissioner, Bratton served as the chief of the LAPD from 2002 to 2009. Using the revolutionary CompStat system, which crunches crime numbers and determines where incidents are likely to occur, he helped lower crime within the city for seven consecutive years.

But data now shows that those numbers were significantly skewed by police — and that the number of violent offenses in LA was actually 7 percent higher than what authorities reported during that period, the Times reports.

Serious assault cases were also 16 percent higher.

Despite the error, the Times says violent crime still showed a decline from 2005 to 2012.

LAPD officials have confirmed the findings and admitted that they were working to fix the problem.

“We know this can have a corrosive effect on the public’s trust of our reporting,” said Assistant Chief Michel Moore, who is in charge of the LAPD’s system for tracking crime.

“That’s why we are committed to…eliminating as much of the error as possible.” he explained.

When asked about the Times’ story and whether he’s concerned the underreporting is now happening in the Big Apple, a spokesman for Mayor de Blasio said, “The Mayor has complete confidence in Commissioner Bratton’s leadership. He has led the effort to make New York City the safest large city in the country.”

But John Eterno, a retired NYPD police captain and professor who studied NYPD crimes stats through 2012, argues otherwise.

“I talk with the officers who are still out there and they tell me these practices are continuing,” he told The Post, claiming “the pressures come from Compstat, from headquarters, and indirectly filter down through the rank and file.”

“They constantly put themselves in a box when they promise the numbers are going to continue to go down,” Eterno added. “It becomes a political imperative to make sure those numbers continue to come down.”

Eterno also cited the Post’s coverage on stat manipulation in the past as proof that the NYPD is in fact misclassifying crimes to make the numbers seem lower.

“These are clear examples that the numbers are still being gamed under Bratton,” he said. “It’s even more of an imperative for him now because he’s working under a new policy of stop and frisk where he can no longer use that tack. Also, he’s claiming with de Blasio that crime will go down without abusing that tactic.”

Nineteen supervisors at the 40th Precinct in Motthaven were slapped with disciplinary charges in July after a four-month audit by the NYPD’s Quality Assurance Division discovered that they had cooked the books in 2014 on 55 out of 1,558 crime reports.

The adjustment ultimately made it appear as if crime in the area was down 14 percent, instead of the actual 11.4 percent.

After the story broke, Bratton personally paid a visit to the station house — urging officers to report a crime “as it is” and to “follow the letter of the law,” according to police sources.

The precinct’s commanding officer, Deputy Inspector Lorenzo Johnson, was later reassigned and slapped with departmental charges.

A month earlier, The Post revealed that an NYPD transit boss in Union Square had been transferred to the 47th Precinct in The Bronx after he was caught trying to underreport crimes, including robberies and thefts.

He had even attempted to bully victims into downgrading their complaints and discouraged others from filing reports, sources said.

In order to discover the LAPD’s false reporting, the Times used a computer algorithm to analyze crime data from 2012 to 2013 that they obtained from an investigation they did on the department last year.

That report ultimately uncovered widespread errors in the way serious assaults were classified and forced LAPD Chief Charlie Beck to publicly admit the wrongdoings.

After discovering that certain words identified a crime as a serious or minor assault, the Times went over the data from 2005 to 2012 and back-checked each incident with reporters for accuracy.

They eventually discovered that the LAPD had consistently distorted the numbers from year to year and that serious crimes had been dismissed as minor offenses.

Many of these incidents in fact resulted in serious injuries — including a case in 2009 in which a man stabbed his girlfriend with a 6-inch kitchen knife, according to the Times.

While the boyfriend was later found guilty of assault with a deadly weapon, the attack was listed as a “simple assault” in the LAPD’s crime database.

Shortly after acknowledging the problems within the department last year, Beck made several changes to the way crimes were recorded.

The LAPD launched a team of detectives, dubbed the Data Integrity Unit, which was tasked with improving the quality of police reporting.

In addition to retraining hundreds of officers in charge of classifying crimes, the group conducted unscheduled spot checks on crime reports from each of the department’s regional divisions.

They also used detailed diagrams called “decision trees” to give station officers a step-by-step lesson plan on how to classify crimes and approve officers’ reports, the Times reports.

But despite all this, an internal police audit released by the LAPD earlier this week found that officers were still fudging their reports last year — with aggravated assaults appearing to be 23 percent lower than what they actually were.

Police officials later claimed that the data had been obtained before their reforms were in place, adding that they expect the errors to decline in the future.

Several current and retired LAPD officers have blamed the misconstrued numbers on the immense pressure from division captains to meet their crime reduction goals, according to the Times.

While Moore agrees that senior police officials can often be “condescending” and give “pressure-cooked” speeches during meetings, he insisted that placing the higher-ups in charge of crime trends was necessary.

“Is there pressure today? Absolutely,” he said. “We hold our people to high standards. Our issue is to do so respectfully and in a manner that provides people with their dignity.”