The head of the city’s sergeants union slammed Mayor Bill de Blasio and Police Commissioner James O’Neill for playing politics with policing, warning that crime will return to the bad old days.

“We continue to do the wrong thing because of the politics,” said SBA president Ed Mullins, laying the blame at not just the current top brass — but former commissioner Bill Bratton as well.

Mullins, who took aim at the administration during The Cats Roundtable on AM 970 in New York hosted by John Catsimatidis, called the current state of the city a “shame.”

“It doesn’t have to be this way,” he said.

“I laugh when I hear the Police Commissioner say this is not the 80s. He’s 100% correct. I agree with him on one thing: It is not the 80s. This is the 70s leading into the 80s. It’s the people of New York City that have no idea what the 80s were like. If this continues, they’re going to find out soon.”

Mullins accused the administration of misleading the public with crime statistics.

“Try telling that to the victims,” he said and pegged part of the issue to the public’s inability to talk about race.

“We have poor people living in poor communities that are allowed to be victims,” he said. “People don’t want to touch the issue of race.”

“I know where this is going. If you continue to blame the cops, you’re going to be living with the criminals.”