Originally published at Daily Kos 

Tennis superstar Serena Williams joined the growing chorus of prominent black voices speaking out against police violence against African-Americans with a Facebook post expressing fear of “driving while black.”

Williams wrote that she felt compelled to speak out after asking her 18-year-old nephew to drive her to meetings and seeing police on the road. “I quickly checked to see if he was obliging by the speed limit. Than I remembered that horrible video of the woman in the car when a cop shot her boyfriend,” she said, referring to Lavish Reynolds, girlfriend of 32-year-old Philando Castile, who was reportedly complying with an officer’s order to hand over his identification during a stop for a broken tail light in Falcon Height, Minnesota on July 6 when he was shot dead in front of Reynolds and her 4-year-old daughter.

“All of this went through my mind in a matter of seconds,” Williams wrote. “I even regretted not driving myself. I would never forgive myself if something happened to my nephew. He’s so innocent. So were all ‘the others.'”

“Why did I have to think about this in 2016? Have we not gone through enough, opened so many doors, impacted billions of lives?” she asked. “But I realized we must stride on —  for it’s not how far we have come but how much further still we have to go. I than [sic] wondered than [sic] have I spoken up? I had to take a look at me. What about my nephews? What if I have a son and what about my daughters?”

“As Dr. Martin Luther King said ‘There comes a time when silence is betrayal,'” she continued, a reference to King’s April 4, 1967 “Beyond Vietnam” speech in which he called the United States government “the greatest purveyor of violence in the world today.”

Williams’ post ends with a vow: “I won’t be silent.”

The winner of 22 Major titles — the most in Open Era history — spoke out as protests continued over the fatal police shootings of Keith Lamont Scott in Charlotte, North Carolina and Terence Crutcher in Tulsa, Oklahoma. Tulsa officer Betty Shelby has been charged with manslaughter in connection with Crutcher’s death.

Williams’ post came hours before police in El Cajon, California shot and killed 30-year-old Alfred Olango, an unarmed black man whose sister had called 911 seeking help with a mental health emergency. She joins a growing chorus of black voices protesting or expressing concern over the many police shootings of black people, many of them unarmed. Many professional, college and high school athletes, led by San Francisco 49ers quarterback Colin Kaepernick, have been refusing to stand during the national anthem before games and matches, while black Americans from President Barack Obama to Hollywood celebrities, police officers and Black Lives Matter activists, have condemned what many call racist police violence while calling for systemic change to address the issue.

“We have seen tragedies like this too many times,” President Obama said in July following the Alton Sterling and Castile shootings. “All of us as Americans should be troubled by these shootings. These are not isolated incidents, they are symptomatic of a broader set of racial disparities that exist in our criminal justice system.”

“African-Americans are 30 percent more likely than whites to be pulled over,” the president noted. “After being pulled over, African-Americans and Hispanics are three times more likely to be searched. Last year, African-Americans were shot by police at more than twice the rate of whites.”

While blacks drivers are much more likely to be stopped by police, officers searching vehicles find less guns and drugs on blacks than on whites, according to a 2013 federal survey.

In the wake of some of the most recent police shootings of black people, a report by the United Nations Working Group of Experts on People of African Descent stated that “contemporary police killings and the trauma that they create are reminiscent of the past racial terror of lynching.”

“In particular, the legacy of colonial history, enslavement, racial subordination and segregation, racial terrorism and racial inequality in the United States remains a serious challenge, as there has been no real commitment to reparations and to truth and reconciliation for people of African descent,” the report said, adding that “impunity for State violence has resulted in the current human rights crisis and must be addressed as a matter of urgency.”