Williams, who is president of a police employee group representing minority officers, said the exposure of blatant racism within the department is causing her members to fear for their safety.
"After all, we need to call for backup and we need to know that it's going to come when we call," she said.
Throughout her 26-year career, Williams said, she has seen institutional racism in the SFPD.
"I have seen that the disciplinary procedures vary according to if you are part of what they call the 'good old boys group,' " she said, referring to officers with generational ties to the department and those who attended certain schools in San Francisco.
"Or perhaps something happened and you kept your mouth shut, and then you get a free buy, or what I call the halo effect, the freeway treatment, and you continue to advance," Williams said.
Williams was the first of several witnesses to raise the subject of the San Francisco Police Officers Association, the union representing all the department's cops, as well as what she called its insensitivity to minority officers and communities.
"The Police Officers Association has been insensitive to the needs and the working conditions of the minority officer," Williams said. "They just don’t get it. They’re constantly antagonizing disenfranchised communities. ... With the stance that the San Francisco Police Officers Association has taken, they have shown that they have very much disregard for the black officers in particular and they have shown disregard for minority communities."
POA president Martin Halloran told KQED Saturday that he wholeheartedly disagrees with Williams.
"I would challenge Ms. Willams to find another police organization that does more outreach to minority communities," he said, "including her own."
Halloran said a new $5,000 grant supporting access to healthy food in Hunters Point is just one example of approximately $200,000 per year the organization donates to charitable causes.
But its relationship with Gascón's blue-ribbon panel has been icy. The association issued a departmentwide memo instructing any officer who was approached by the panel to contact the union, according to sources working with the panel.
"The POA has indicated it wants us to go through them to coordinate these interviews," panel legal counsel Jerome Roth said. "We are not inclined to do that. We believe it’s more important to speak with officers directly and not through the filter of the POA."
Halloran said the association asked "as a courtesy" to be notified when the panel reaches out to any officers.
"They have often not complied with that," he said.
Jeff Godown, who served briefly as the SFPD's interim chief, testified about "institutional pushback" when he came to the department to improve crime data collection and institute a CompStat program.
"I was kind of taken aback by the fact that the San Francisco Police Department at the time I came here in 2009 was as rudimentary as they were when it came to looking at crime data," said Godown, who is now chief of the Oakland schools police force.
"I had not even stepped into the city, and I had received calls from reporters from San Francisco because the department was concerned that there was going to be a CompStat process implemented within the department and they were going to be held accountable," Godown said.
The Police Department has repeatedly been criticized for its statistics collection. CompStat reports currently available on the Police Department's website include just two months of data -- October and November of 2015.
Halloran said Godown and Gascón came to San Francisco pushing CompStat from a "bully pulpit ... ramming it down our throats." He said he supports CompStat's data collection, though, and "has no reason to believe it's not working well."
Office of Citizen Complaints Director Joyce Hicks told the panel that her office received 250 complaints that contained at least one allegation of racial bias since 2011, but the office sustained none of those complaints.
"Racial bias is very difficult to prove," she said. "It is frustrating in light of today’s climate. It is painful."
Hicks said if and when the police in San Francisco are equipped with body cameras, allegations of racism may be easier to prove or disprove. She spoke very slowly, seeming to choose her words carefully, when panel member LaDoris Cordell asked about OCC's relationship with the police officers union.
"If there is an issue that they identify, particularly around interviewing officers, they will contact the OCC," Hicks said. "We do periodically meet with the POA to hear their concerns. I have an open-door policy, and while I may not agree with philosophies, I will listen."
The panel tasked attorney Robert Tarun with investigating the SFPD's compliance with Brady v. Maryland, a far-reaching U.S. Supreme Court ruling that requires prosecutors to turn exculpatory evidence over to defense attorneys. In practice, police departments generally keep a "Brady list," with the names of officers whose past misconduct makes them susceptible to defense challenges if they're called to testify.
"We sought to interview three attorneys -- not police officers, attorneys -- in the San Francisco Police Department, and each declined to be interviewed," Tarun said. "We also asked for Brady policies and Brady training materials of the Police Department, and we have not received any of that material to date."
He said department Brady policies appear to include only guidelines for officer personnel files, prompting questions from panel member Dickran Tevrizian.
"The San Francisco Police Department only tracks personnel issues with regards to Brady, but doesn’t track other exculpatory information? That’s a major issue," Tevrizian said.
Tarun said that's what he could tell, given that the SFPD refused to talk to him.
"They’re not stepping forward and telling you what they’re doing," Tevrizian said.
Roth told the panel of another instance in which the SFPD has been unresponsive. He said the panel filed a public records act request with the department for documents in 30 separate categories in mid-December, and SFPD is now well beyond the time limit under state law to respond.
"They responded to approximately three," Roth said. "They provided some information, most of it public documentation. With respect to the documents they withheld, they did not redact as the act requires, rather they provided no documentation. And then with respect to 22 categories, we got no response at all."
Roth said the panel has filed a complaint with the San Francisco Sunshine Ordinance Task Force and is pursuing other avenues to force the SFPD to release public information.