WASHINGTON (Reuters) - The chairman of the U.S. House Transportation and Infrastructure Committee on Friday said Boeing Co must shake-up its management team and Congress must reform how new airplanes are certified following the disclosure of internal messages about the 737 MAX involved in two deadly crashes.

FILE PHOTO: The Boeing logo is displayed on a screen, at the New York Stock Exchange (NYSE) in New York, U.S., August 7, 2019. REUTERS/Brendan McDermid/File Photo

Representative Peter DeFazio, a Democrat, sharply criticized the largest U.S. airplane manufacturer after instant messages between a former senior pilot and another employee suggested the company may have unintentionally misled regulators and experienced significant issues with a key safety system known as MCAS tied to the two fatal crashes that led to the grounding of Boeing’s best-selling plane.

The Federal Aviation Administration (FAA) said Boeing failed to turn over the internal messages for months, and demanded an explanation.

“It goes far beyond one individual. They can’t hang him and say he’s responsible. This was cultural,” DeFazio said in a Reuters interview on Friday. “Boeing’s got to clean up its culture and I don’t think you can clean it up with the people who were in charge when this all unfolded.”

Boeing spokesman Gordon Johndroe said the company “will continue to cooperate with the committee as it continues its investigation. And we will continue to follow the direction of the FAA and other global regulators, as we work to safely return the 737 MAX to service.”

DeFazio said Boeing should “look closely at their compensation decisions, which is tying decisions they are making to Wall Street instead of making the safest and best aircraft possible.”

The instant messages between Mark Forkner, who was then the chief technical pilot for the 737 MAX, and a colleague, said Forkner “basically lied to the regulators (unknowingly)” and added MCAS had “fundamental” performance issues.

DeFazio says Boeing has not been honest with the committee despite turning over hundreds of thousands of pages.

Boeing chief executive Dennis Muillenburg will testify before the Senate Commerce Committee on Oct. 29 and before DeFazio’s panel on Oct. 30.

Senator Roger Wicker, who chairs the Senate Commerce Committee, said in a statement the documents are “disturbing” and pledged to get “a thorough explanation that provides a more complete picture of what is being discussed.”

Asked if he thought Muillenburg should step down, DeFazio said: “I don’t know that I would just isolate it to him.”

DeFazio said the latest revelations convince him that Congress must reform how the FAA certifies new airplanes by designating some certification tasks to Boeing itself. In the case of the 737 MAX, it designated more than 40% of the tasks to Boeing, including MCAS.

“We have to fix the law, which failed us in this case,” DeFazio said, noting there is an ongoing criminal probe. “I can’t put any of these people in jail.”

The 737 MAX certification was faulted last week by a panel of international regulators, which said the FAA had limited oversight of Boeing’s certification efforts and found signs of “undue pressure” on Boeing employees.

Initially, DeFazio was not certain Congress needed to change the law. “I am now dead certain the law has to change,” DeFazio said, adding he has not decided how it should be reformed.