Former president Barack Obama is urging those angered by the death of George Floyd to focus their efforts on state and local elections and to push officials on those levels for specific reforms to the criminal justice system.

"If, going forward, we can channel our justifiable anger into peaceful, sustained, and effective action, then this moment can be a real turning point in our nation's long journey to live up to our highest ideals," Obama said in a Medium post on Monday.

At a time when protesters are gathering nightly outside the White House, Obama said those seeking change should be fighting for a president and other federal officials who recognize "the corrosive role that racism plays in our society and want to do something about it."

But he argued that "the elected officials who matter most in reforming police departments and the criminal justice system work at the state and local levels."

"It's mayors and county executives that appoint most police chiefs and negotiate collective bargaining agreements with police unions," Obama wrote. "It's district attorneys and state's attorneys that decide whether or not to investigate and ultimately charge those involved in police misconduct. Those are all elected positions."

Obama also cited documents developed during his presidency and by the Obama Foundation that he says can provide guidance on reforms to seek.

"The more specific we can make demands for criminal justice and police reform, the harder it will be for elected officials to just offer lip service to the cause and then fall back into business as usual once protests have gone away," he wrote.

In the post, he said the waves of protests have been driven by “genuine and legitimate frustration,” but he also urged those seeking reforms not to “excuse violence, or rationalize it, or participate in it.”