Mortgages lenders controlled by Warren Buffett's Berkshire Hathaway are making the vast majority of their home loans to white borrowers in a way that former prosecutors say may violate the Fair Housing Act, a 50-year-old law that banned racial discrimination in lending.

That's according to a new exposé by Reveal from The Center for Investigative Reporting.

The non-profit newsroom examined the records of three lenders under Berkshire Hathaway's corporate umbrella. It found the companies -- HomeServices Lending, Prosperity Home Mortgage, and Trident Mortgage Corporation --- employed overwhelmingly white teams of loan officers, placed their offices in white neighborhoods, and concentrated their lending in white neighborhoods.

Among their biggest markets are Atlanta, Philadelphia, and Washington, DC, where a majority of residents are people of color.