Oakland's mayor was blunt:

"I'm here to run a police department, not a frat house," Libby Schaaf said at a press conference on Friday.

A number of police officers in the California city have been accused of sexual misconduct; others have allegedly sent racist texts. Now three police chiefs have resigned over the course of just over a week.

"This is the appropriate time to install civilian oversight in this police department," Schaaf said, according to The Associated Press. Schaaf announced that City Administrator Sabrina Landreth will now be handling personnel and disciplinary matters for the department.

Local leaders are calling for a complete overhaul of the police department, Danielle Karson reports for NPR.

"A teenager is at the center of the scandal," Karson says. Eighteen-year old Celeste Guap says she had sex with more than two dozen police officers, partly in exchange for information on how to avoid undercover prostitution stings. She had sex with officers when she was a minor, she says.

Separately, a number of officers have been accused of sending racist texts. The officers in question are black, Reuters reports, and are currently under investigation.

The scandals have led to upheaval at the department. Police Chief Sean Whent resigned on June 9. The interim police chief, Ben Fairow, was abruptly replaced on Wednesday after Schaaf learned "unspecified information that led her to lose confidence in his ability to lead the beleaguered department," as the AP puts it.

And the third chief — acting police Chief Paul Figueroa — stepped down on Friday, with Schaaf saying his decision was unrelated to the scandals, the AP reports.

The mayor denounced the police department's "toxic, macho culture" and said, "I want to assure the citizens of Oakland that we are hellbent on rooting out this disgusting culture," the AP reports.

"The Oakland PD is no stranger to controversy," Danielle notes. The police department was placed under federal oversight in 2003 over high-profile police brutality and racial profiling cases.

That oversight continues today.

Earlier this year, as the East Bay Times reported, the police department appeared to be on track for the federal oversight to finally be relaxed, with a shift toward "ensuring that the police department doesn't backtrack on reforms."

But a two-year-long Stanford study, released this past week, found that African-American men in Oakland are four times more likely than white men to be searched during a traffic stop, and African-American people are more likely to be handcuffed by police than whites are.

Then-Acting Chief Figueroa, responding to the study last week, told PBS, "we're at a position in reform, not only locally, but nationally, that we're finally getting to the point where we have the data, where we can take some real action."

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