The Denver Police Department has discovered problems with 1,000 of its crime reports, prompting an investigation into who is responsible for the errors and whether someone intentionally fudged the numbers.

Inaccurate data or false reporting can damage a department’s credibility, said Jim Ponzi, an associate professor of criminology at Regis University in Denver who has researched crime reporting and its impact across the United States.

“The biggest thing of all is how do you stop crime if your statistics are inaccurate?” Ponzi said Tuesday. “Where do you dedicate your resources if you don’t have baseline data?”

For now, the department is unable to finalize its 2017 annual crime report as it digs into why the numbers are flawed and who is responsible, said Sonny Jackson, a police department spokesman.

“If there’s something wrong, we’ll drill down on it,” Jackson said. “The chief believes they’ve got to be as accurate as they can be.”

Jackson would not specify which categories of crime statistics are flawed or from which of the city’s six police districts the reports originated. The audit found about 1,000 crime reports that were problematic, about 1 percent of the total crime reports filed in 2017, Jackson said.

Crime data is important to a city on multiple levels. It can affect everything from where a police department assigns its officers to home prices in neighborhoods where crime may appear rampant. The numbers also can influence decisions about promotions and commendations within police departments as commanders who can show decreased crime in their districts are rewarded, Ponzi said.

Denver police on Jan. 11 issued a news release to report that employees in its data analysis unit had “discovered some anomalies in how cases were being classified.” Chief Robert White ordered an audit of the relevant citywide crime statistics. The department has never explained what specific anomalies were found.

“One of the most crucial elements of our relationship with the community is trust,” White was quoted as saying in the news release. “Therefore, it is critical that we are transparent and accurate with the information we maintain and report.”

On Monday, CBS4 reported on the internal investigation and said the crime reports were downgraded in a way that improved department crime statistics. Intentionally reporting false crime data could be criminal under Colorado laws.

Nick Mitchell, the city’s police watchdog, said his office will monitor the investigation with the goal of ensuring the allegations are thoroughly investigated.

“The accuracy of crime data is essential to public confidence,” Mitchell said.

The Denver Police Department reports crime data through two databases. The Uniform Crime Data reporting is delivered to the Colorado Bureau of Investigation and the FBI. The National Incident-Based Reporting System provides more specific data for the department.

On its website, the department has not updated either database since November.

According to the UCR data for last January through November, violent crime increased in the city by 5.2 percent and serious property crimes rose 1.5 percent over the same period in 2016.

According to the NIBRS report, crimes against persons dropped .3 percent for the 11 months reported in 2017 when compared to 2016, and property crimes rose 1.9 percent during the same period.

Police departments began relying heavily on crime data in the mid-1990s to decide where to focus resources and to predict trends in specific neighborhoods. And the data became a way for police chiefs to hold their commanders accountable.

In Denver, police hold regular meetings to discuss crime data, and commanders of the city’s six police districts must answer hard questions how they are responding to trends.

The pressure can be intense, Ponzi said, and it can lead to problems.

“When you call people on the carpet and embarrass them in front of their peers and hold their commands over their heads, it’s human nature to do something about it,” he said.

Jackson would not speculate about how far up the chain of command the problem may rise. It’s too early in the investigation, he said.

“We may find that it’s a training issue,” Jackson said.

Ponzi was skeptical that the inconsistencies were linked to training. Field officers’ reports are approved by supervisors who should be watching for errors in classifying crimes and then talking to officers on the spot when they find them, he said.

Ponzi has documented dozens of examples of bad data-keeping at departments across the United States, including past issues in Denver.

In 2005, inaccurate stats led Denver to pass an unconstitutional auto-theft ordinance that was based on bogus numbers, he said. And in 2012, media reported that 12,000 reports had been missing from the city’s crime mapping website since 2009. Those missing numbers were blamed on a computer error.

Officers and their commanders can find ways to “mischaracterize reports” so that they don’t show up in official databases, Ponzi said.

In Denver, that could be through a “letter to detective” where a person’s crime report is submitted for official record on a need-to-know basis but is not counted as a crime, said Ponzi, a former Denver police lieutenant.

“If they can find a way to mischaracterize a crime into something not reported to the FBI, the crime never shows up,” he said. “There are many purposes to doing this. The biggest is to downgrade serious crimes so both your police department and city look better to the public.”