Mayor London Breed recently announced that she had accepted assistance with car repairs from former Public Works Director Mohammed Nuru, who resigned this month after his arrest in a federal corruption investigation. Breed’s car is old enough to vote — and apparently still not working properly — and she has been close friends with Nuru for decades. Nonetheless, it was a mistake for the mayor to accept the gift and let a long-standing personal relationship distract from her professional responsibilities as San Francisco’s chief executive.

The mayor has clearly acknowledged the error; as she said, she is a human being, and human beings make mistakes. Most voters seem to understand that and appreciate her openness and contrition.

The same, unfortunately, cannot be said for Supervisor Hillary Ronen and the small group of political figures who have been trying to tear down Breed since before she became mayor. Sensing an opportunity to attack her, they suddenly proclaimed themselves guardians against civic corruption. And Ronen almost immediately declared that Breed should resign. This was laughable on its face and drenched with hypocrisy when subjected to even passing scrutiny.

Former mayor and supervisor and current venture capitalist Mark Farrell faced a $191,000 Ethics Commission fine after his 2010 supervisorial campaign was charged with coordinating with an independent expenditure campaign that was not independent at all. (The fine was reduced after Farrell sued.) Did Ronen call on Farrell to resign? Did she bemoan corruption in city government on that occasion? No, she helped appoint Farrell mayor.

Former Supervisor John Avalos was fined $12,000 by the Ethics Commission on charges that his mayoral campaign misreported over $26,000 and failed to maintain accurate records for over $391,000. He also had an extramarital affair with an aide (speaking of an inappropriate overlap of personal and professional relationships). When the affair came to light in 2014, Avalos said, “I felt it was most appropriate for her to find employment outside this office,” suggesting the aide lost her job for dating her boss, i.e. him. Did Ronen call for Avalos’ resignation? Did she question his fitness for office? No — in fact, she is running on a slate with him as I write this.

But surely Ronen has shown purity in her own affairs? Again, no. The supervisor continued fundraising for a ballot measure after she had decided to withdraw it, misleading supporters into thinking the campaign was still happening. And in 2018, she led an effort to appropriate extra city funds to the Public Defender’s Office unit that her husband manages.

These are a few of many examples of the double standard some politicians apply to the mayor on one hand and to their friends and allies on the other. Sadly, African American leaders often face such a double standard.

When state Treasurer Fiona Ma and San Jose Mayor Sam Liccardo endorsed Michael Bloomberg for president, for example, plenty of people may have disagreed with their choice, but no one questioned their character. Yet when Breed and the African American mayor of Stockton, Michael Tubbs, endorsed Bloomberg, the distressingly common response on social media and elsewhere was, in essence, “How much did Bloomberg pay them? What did they get for this?”

There is a casual, almost accepted racism in constantly suggesting black leaders are corrupt. It is wrong, and it is far too prevalent.

Now is not the time for racial stereotypes or politically motivated hyperventilating in San Francisco. We have far too much of both in our national discourse. Now is the time for introspection, collaboration and a focus on the substantive issues we face.

Malia Cohen is a member of the state Board of Equalization and a former San Francisco supervisor.