Excessive use of force has long been a problem for the Oakland Police Department, leading to civic distrust, costly lawsuits and the nation’s longest-running federal intervention.

Despite several recent officer-involved shootings, a Chronicle analysis of Oakland Police Department data shows such incidents are becoming less common. Officer-involved shootings, excessive force complaints and incidents in which officers used force have all declined precipitously over the past three years in Oakland.

Save any major slipup, the department, which has been monitored by a federal court since 2003, is expected to soon regain its autonomy. It would save the city millions and help the law enforcement agency shed its reputation as one of America’s most dysfunctional.

But if history is any indication, maintaining the gains achieved under federal oversight could be just as daunting as securing them.

“We have seen improvement, but the jury is still out on whether it will be sustainable,” said civil rights attorney Jim Chanin, who has helped oversee the department’s reforms. “There are some positive signs that it will be, but we don’t know yet.”

Related story: Sharp downturn in use of force at Oakland Police Department

OPD by the numbers

The Oakland Police Department averaged roughly eight officer-involved shootings per year between 2000 and 2012. There have been just six over the past 24 months, including the uptick this summer — a decline of more than 60 percent in shootings from the prior decade’s average.

Alameda County sheriff’s deputies and Highway Patrol officers were involved in four shootings in Oakland over the same time frame, all of them fatal, despite having fewer cops on the streets, according to data obtained through a public records request.

A review of more than 22,000 use-of-force incidents also shows less severe altercations between police and the public are on the decline.

Between 2009 and 2014, the number of use-of-force incidents recorded by the department dropped four-fold, from 3,902 to 895. There were 49 incidents reported in July — the lowest monthly count in the reviewed time frame.

If current trends continue, aggressive interactions with the public would drop to 630 in 2015.

The falling numbers are a good indication that police-community relations are improving, according to Barry Krisberg, a UC Berkeley criminologist. “Oakland has been pretty quiet compared to the 600 bullets fired in Stockton, or some pretty horrendous lethal-force incidents in San Jose,” he said.

Use-of-force complaints, which include a range of behaviors from grabbing suspects by the hair or bending their wrist to choke holds and shootings, also dipped more than 40 percent from 2013 through 2014. Grievances filed with the Citizens’ Police Review Board — which investigates some excessive-force allegations — steadily declined from a high of 90 in 2009 to 15 in 2014.

Meanwhile, arrests have remained relatively steady, suggesting the positive numbers may not be the result of lax policing.

A long time coming

Along with improvements in community relations, certain crimes have also dropped. Homicides fell from 126 in 2012 to 80 in 2014. The numbers are on pace to be about the same this year. Serious crimes fell 8 percent over the same time period.

“We have had three successive years of double-digit reductions in shootings, so we’re definitely having an impact,” Oakland Police Chief Sean Whent said in an interview with The Chronicle. “But it’s still a high-crime city and we have a lot more work to do.”

The improvements have been a long time coming.

A handful of law enforcement agencies have struggled to complete federal mandates to reform, but none has been under oversight for longer than Oakland, which entered what is known as the Negotiated Settlement Agreement more than a decade ago.

Misconduct payouts

The department’s difficulties have provoked ire from court-appointed monitors and some community members.

The frequency with which officers drew and pointed guns at suspects, the handling of the Occupy Oakland protests — which resulted in hefty misconduct settlements including a $4.5 million payment to an Iraq War veteran shot in the face with a tear gas canister — and inability of the department to punish bad cops were all regularly criticized by courts and city leaders.

Some feared the department would never turn a new leaf.

Things began to change, though, in 2013 after Whent was appointed chief. He ushered in new use-of-force trainings, updated foot and vehicle pursuit policies to keep officers out of dangerous situations and oversaw the full implementation of the body camera program — which has been attributed to improved interactions between police and civilians.

“Oakland needed fresh leadership and I think they got it,” Krisberg said. “There’s no reason to think that police-community relations, which had deteriorated so badly, could have fixed themselves.”

Maintaining the gains

Oakland police still need to iron out some lingering suggestions from the federal monitors, including expanding the department’s use-of-force review board, more thoroughly tracking vehicle-stop data and addressing the issue of fired cops being re-hired through arbitration. Still, the department and some civic leaders believe an end of federal oversight is on the horizon.

The prospect elicits both hope and anxiety.

“There is a long history of important reforms that, for one reason or another, simply faded away,” said Samuel Walker, a criminologist at the University of Nebraska who has studied the OPD. “This has been a problem for the entire history of policing.”

Anticorruption policies implemented at the New York Police Department in the 1970s helped clean up the force, but the reforms didn’t last. In 1993, a special mayoral panel determined that NYPD “had failed at every level to uproot corruption,” and that it “concealed lawlessness by police officers,” according to the New York Times.

The San Diego Police Department exemplified best-practice policing throughout the 1980s and 1990s, Walker said, but it was recently rocked by a sexual assault scandal. Ten officers were investigated for rape, domestic violence, driving under the influence and sexual battery during a three-month span in 2011, according to a U.S. Department of Justice audit; six were ultimately arrested. More sexual assault cases piled up in 2014 and 2015.

“Community leaders in Oakland have to be diligent, they can’t just say, ‘The war is over,’ ” Walker said. “The department will be on its own, so it’s up to Oakland to ensure that they don’t slide back.”

Some have proposed creating a police commission — a civilian board that sets policy and conducts disciplinary hearings for misconduct. In theory, a commission would add an extra layer of oversight if and when the monitors pack up.

An insurance policy

“After having spent so many millions of dollars and so much time, why would we not want to make sure there’s a protection in place to keep us from losing our investment,” said Rashidah Grinage, former executive director of Oakland police watchdog group PUEBLO.

Whent thinks improvements can be cemented in without a commission.

He points to his department’s 700 body cameras — roughly the same number as sworn officers — and the fact the city has set aside money for two new auditors at the Office of the Inspector General, which keeps tabs on the Police Department. He also said the department plans to make a civilian the head of internal affairs.

All should help keep the progress intact, he noted.

“That would be the biggest disaster; if we were to end the Negotiated Settlement Agreement and then all of the sudden go back to something else,” Whent said. “It really is my goal that the day it ends, nobody recognizes any difference.”

Joaquin Palomino is a San Francisco Chronicle staff writer. E-mail: jpalomino@sfchronicle.com; Twitter: @joaquinpalomino