A long-awaited report ordered by the police commissioner in New York has found deficiencies in the Police Department’s efforts to detect whether its crime statistics are being manipulated.

The report made numerous recommendations, including the suggestion that the Police Department should do more to hold supervisors accountable for “egregious” mistakes in how crimes are classified, even if they did not make the mistakes. The report urged the department’s auditing staff to “be more proactive in pursuing errors that suggest intentional downgrading.”

Commissioner Raymond W. Kelly said the department had “adopted all of these recommendations.”

The report was released on Tuesday, more than two years after Mr. Kelly empaneled a committee of former federal prosecutors to review the department’s internal crime-reporting system.

The committee’s report did not directly address how often such manipulation occurred, but it identified vulnerabilities in the department’s system for auditing the integrity of its crime statistics.