Southwest and Frontier are being sued by the DOT for consistently late flights.

• The suit alleges Southwest Airlines repeatedly operated late-arriving flights in 2022.

On Wednesday, the Department of Transportation sued the airline, accusing it of consistently delayed flights, and imposed a fine for tardy arrivals.

The lawsuit follows a DOT fine on for similar allegations.

The Biden administration has been more stringent in consumer protection than previous administrations, and the lawsuit and fines will be enforced at the end of the administration.

Nearly 200 flights from Chicago Midway International Airport to Oakland, Calif. and from Baltimore to Cleveland arrived late between April and August 2022, according to the DOT.

The DOT stated that the airline was responsible for over 90% of the flight delays, which were chronically delayed for five consecutive months.

Southwest didn't immediately respond to a request for comment.

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