The FCC’s inspector general is investigating whether Ajit Pai, the agency’s chairman, improperly used his power to benefit Sinclair Broadcasting. The television conglomerate has pushed its local news stations to run commentary segments that praise the Trump administration, and is currently seeking a merger which would vastly expand its reach.

As reported by the New York Times, the investigation is focused on Pai’s decision to relax rules limiting the ownership of television stations by a single company. Pai reinstated a technologically obsolete rule known as the UHF discount, giving some television stations less weight in calculating whether a single owner exceeds a legal cap limiting its reach to 39% of the U.S. population.

That rule change effectively creates a loophole that would allow Sinclair’s planned $3.9 billion acquisition of Tribune Media, which would put Sinclair stations in 72% of U.S. households. That would represent a historic level of media consolidation, which has long been criticized as a threat to healthy democratic discourse. Despite the spread of online news, television is still the dominant source of news for Americans.

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One major backer of the investigation into Pai’s decision is Frank Pallone, a Democratic Congressman from New Jersey. Pallone told the Times that “for months I have been trying to get to the bottom of the allegations about Chairman Pai’s relationship with Sinclair Broadcasting.” Some of those allegations were unearthed in a Times investigation last August, which found that Pai had communicated closely with Sinclair executives as he rolled back rules, and that his decisions often aligned closely with Sinclair priorities.