In an appearance on Fox News Channel’s “Hannity” with fill-in host and Daily Caller editor in chief Tucker Carlson, author Thomas Sowell argued that the federal minimum wage law has been used to undermine companies that employ blacks.

In the fourth quarter of 2012, the black unemployment rate was more than double the rate for whites. But prior to the 1930s, Sowell said, black unemployment was actually lower than white unemployment.

“What changed was the government intervention into the labor market,” Sowell said. “1930 was the last year in which there was no federal minimum wage. They brought in the Davis Bacon Act.”

Addressing the high-profile affirmative action case Fisher v. University of Texas currently before the Supreme Court, Sowell noted that the court has always left openings to allow for racial quotas.

“It all depends whether the Supreme Court wants to give a clear decision one way or the other, or whether they want to do what they’ve been doing now for more than 30 years, saying pious things, that you can’t have quotas, but leaving wiggle rooms that you can have quotas, so long as you don’t call them quotas,” he said.

Sowell denied that affirmative action has been generally beneficial for blacks.

“There’s a marvelous study done showing that when they banned affirmative action in California, the University of California system, blacks began to graduate at a much higher rate than before. … Before you could flunk out of Berkeley or UCLA, which does you no good, [but] now you could graduate from Davis or Santa Cruz and go on to a career.”

Follow Jeff on Twitter