Just weeks after a legislator voiced concern that a shrinking airline industry has perpetuated potential anti-competitive behavior aimed at keeping the price of airfare high, the Department of Justice revealed it is looking into the possibility of collusion between airlines.

The Associated Press reports that the Dept. of Justice opened an antitrust investigation into whether airlines are colluding to grow at a slower pace in an attempt to keep ticket prices high.

A document obtained by the AP shows that the DOJ has requested information from airlines as part of the investigation.

A spokesperson for the Department confirmed that the agency was investigating potential “unlawful coordination” among some airlines, but declined to specify which ones.

According to the AP, American Airlines, Delta Air Lines, Southwest Airlines and United Airlines currently control more than 80% of the airline industry’s seating capacity.

News of the antitrust investigation comes about two weeks after Connecticut Senator Richard Blumenthal sent a letter [PDF] to Assistant U.S. Attorney General William Baer urging the DOJ to investigate possible collusion and anti-competitive actions in the airline industry that could result in higher airfares for consumers.

Blumenthal cited a recent report which found some airlines plan to cut back on the number of seats offered on certain routes in an attempt to boost profits.

“In light of the recent unprecedented level of consolidation in the airline industry, this public display of strategic coordination is highly troubling,” Blumenthal stated in the letter.

Justice Department investigating potential airline collusion [The Associated Press]

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