The Justice Department sued the Trump Management Corporation in 1973, based on evidence gathered by the New York City Human Rights Division. The agency alleged that black people who were told that no apartments were available, while white people were offered units.

After two years, the case was settled. Trump did not have to admit guilt as part of the settlement. He attempted to counter-sue the Justice Department for making false allegations, but it was dismissed by the court.

NPR – Decades-Old Housing Discrimination Case Plagues Donald Trump
The New York Times – Major Landlord Accused Of Antiblack Bias in City
Time – Donald Trump’s 1973 Discrimination Case Really Was Part of Something Larger