Minneapolis police have introduced a new system for tracking crimes and arrests across the city, allowing the public to compare statistics from one month to the next.

In the past, armchair crime analysts had to sift through reams of MStat records — which differ from the FBI's Uniform Crime Reports, which only track the most serious offenses in any particular crime.

The process was time-consuming — the data was released only once a week — and it was difficult, for example, to determine what percentage of the city's robberies in July were committed in the Fifth Precinct compared to the same time last year.

Two dashboards (one for reported crimes, the other for arrests) offer plenty for users to sink their teeth into, Chief Medaria Arradondo said in an e-mailed statement.

"Our strategic analysts and partners with City IT continue to amaze me with their work products, and by providing residents with as much as data as we can, we further our mission of increasing trust, accountability and professional service," Arradondo said. He called the new system "more efficient" and "user-friendly."

Arradondo, who has pledged to bring more transparency to the department, apologized for a weekslong gap in the crime reports, an interruption caused by the retirement of a veteran analyst.

Curious users can now search crimes ranging from homicide to larceny and compare their frequency over the past three years. Query results can be broken down by day, week, quarter or year.

The tools, which are available on the department's insideMPD.com/datadashboard website, will be refreshed every morning and can be exported via the city's open data portal, officials said.

The department also overhauled its weekly online map highlighting instances of gun violence: shootings, ShotSpotter activations and shots-fired calls.

A police spokesman said that analysts are developing tools for data on the number of gunshot victims, "positive" public contacts, suspicious persons and suspicious vehicle stops, and the number of weapons recovered, all of which were previously available.

In August, the department opened a similar online dashboard cataloging traffic and street-stop data, which was hailed by the ACLU as a necessary step "toward becoming more transparent and accountable to the communities it serves."

The online tool shows the demographic characteristics of people detained in traffic and suspicious-persons stops across the city, along with trends in the arrests on curfew and truancy violations.

Libor Jany • 612-673-4064 Twitter: @StribJany