Before Trump came along, the US Govt was making substantial progress in reducing police brutality and violence, particularly as involves the African American community, through the "consent decree" process.
To sell his get tough, law and order BS, Trump almost blindly began the process of dismantling one consent decree and stopped the process entirely. No surprise that we get Abery, Floyd etc., and national riots.
Biden intends to reverse that stoppage and go back to the prior system
https://www.foxnews.com/politics/biden-doj-police-departments-systemic-misconduct
Biden to use DOJ to crack down on police departments engaged in 'systemic misconduct'
Biden intends to return to the Obama administration's embrace of consent decrees for police departments
Many, many good police officers and good cops across the country doing very good work. But, plenty of built in racism and racism in leadership and terrible "comply or die" mindset