They’re going wild, these vibrant young men and women, cheering and chanting. “Who are we?” comes the call. “One-seventy!” is the response.

They are graduates of Oakland Police Department’s 170th academy. They can’t wait to prove themselves worthy to the OPD at a time when the OPD is struggling to prove itself worthy to the public it serves. And so Oakland filmmaker Peter Nicks’ gritty documentary “The Force,” which plumbs the culture of the Oakland Police Department, begins.

Go to our Facebook page for more conversation and news coverage from Oakland and beyond.

Related Articles Police arrest suspect they say was involved in fatal shooting of East Bay teacher

Oakland police chief dismisses ‘boogaloo’ connection based on officer’s attire

DA declines to file charges against Oakland cop accused of stalking, harassment

Oakland police and protesters clash Saturday night

Reward rises for West Oakland fatal shooting information The giddy trainees can’t possibly know what’s in store for them. You wonder if Nicks had any inkling what was awaiting him when he embedded himself in the department, the mayor’s office and the mean streets of Oakland and started rolling film in the fall of 2014.

One of the first voices in the film belongs to then-Chief Sean Whent. “This police department has a history that we have to own up to,” he says. “It’s our legacy.”

It’s a long legacy that includes the 1970s, when Oakland’s department was regarded as a model for other cities to emulate.

Lately? Where would you like to start?

Whent’s comments in the film, intended for public consumption, are measured and considered. Soon enough, Deputy Chief Leronne Armstrong gets his chance to address the trainees in a classroom, a more informal setting. His are words to live by.

“You think, oh, I’m just a lowly police officer — until you do something wrong,” he cautions. “Then you’re the YouTube sensation. One police officer can affect the credibility of a department, of a city. One police officer can have an impact on this whole country.”

You begin to grasp the enormity of the job and the perils of getting it wrong. The film allows viewers to drop in on what-would-you-do? scenarios. The department has trainees approach a man in an interactive video. Does he have a weapon? When do you make your move? “Make all your mistakes in here,” they are told, “so you don’t make any out there.”

These types of issues are common to all law enforcement agencies. OPD, under federal oversight since 2003, caught up in a sex scandal as the film is being shot, has an uneasy relationship with Oakland residents. It’s like officers have one strike against them before they step out of their cruisers. Example: It’s November 2014, and there is a protest in Oakland in response to events in Ferguson, Missouri. OPD officers are there in vests and helmets.

“Bring on more robots,” taunts a protester. “We aren’t scared of (expletive).”

When Whent, hired to reform the department, shows journalists body cam footage from two incidents in 2015, the public won’t trust the account offered by the chief or the press.

“Are you insinuating that there’s possibly a conspiracy involving the entire department and the coroner’s office?” an African-American woman is asked. “Yes,” she says without hesitation.

The summer of 2016 is a blur of police chiefs coming and going — starting with Whent’s resignation. Mayor Libby Schaaf gives her “toxic macho culture” address. (A 2017 report by a federally appointed investigator will conclude Whent failed to properly investigate the sex scandal involving the teen daughter of a police dispatcher. A dozen officers will be fired or suspended without pay.)

Nicks’ cameras record a meeting of residents demanding the formation of a civilian police commission. “We do not believe there are good cops,” one resident says. “We don’t believe that police departments can actually be reformed.” In November 2016, Oakland votes for such a commission, which has power to investigate misconduct and to discipline and fire the chief.

Back to the graduates of the 170, now three-year veterans of OPD. Perhaps they recall the last words from Deputy Chief Armstrong back in 2014:

“What is your legacy going to be?”

Get top headlines in your inbox every afternoon.

Sign up for the free PM Report newsletter.

“The Force” will open Sept. 15 at the Landmark Embarcadero in San Francisco, the Landmark California in Berkeley and the Grand Lake Theater in Oakland.