The FBI has joined the criminal investigation into the certification of the Boeing 737 MAX, lending its considerable resources to an inquiry already being conducted by U.S. Department of Transportation agents, according to people familiar with the matter.

The federal grand jury investigation, based in Washington, D.C., is looking into the certification process that approved the safety of the new Boeing plane, two of which have crashed since October.

The FBI’s Seattle field office lies in proximity to Boeing’s 737 manufacturing plant in Renton, as well as nearby offices of Boeing and Federal Aviation Administration (FAA) officials involved in the certification of the plane.

The investigation, which is being overseen by the U.S. Justice Department’s criminal division and carried out by the Transportation Department’s Inspector General, began in response to information obtained after a Lion Air 737 MAX 8 crashed shortly after takeoff from Jakarta on Oct. 29, killing 189 people, Bloomberg reported earlier this week, citing an unnamed source.

It has widened since then, The Associated Press reported this week, with the grand jury issuing a subpoena on March 11 for information from someone involved in the plane’s development, one day after the crash of an Ethiopian Airlines 737 MAX 8 near Addis Ababa that killed 157 people.

The FBI’s support role was described by people on condition of anonymity because of the confidential nature of the investigation.


Representatives of the Justice Department, the FBI and Transportation Department declined to comment, saying they could neither confirm nor deny an investigation. Boeing declined to comment.

A Seattle Times story on Sunday detailed how FAA managers pushed its engineers to delegate more of the certification process to Boeing itself. The Times story also detailed flaws in an original safety analysis that Boeing delivered to the FAA.

Two days later, Transportation Secretary Elaine Chao took the unusual step of asking the department’s inspector general to conduct a formal audit of the certification process for the MAX. The audit is an administrative action, separate from the criminal investigation.

Criminal investigations into the U.S. aviation industry, including federal oversight of airplane manufacturing and airline operations, are rare — in part because of the longstanding belief that a civil-enforcement system better promotes candid reporting of concerns without fear of criminal repercussions.

Those criminal cases that have occurred have focused on false entries and misrepresentations.

In 1998, Transportation Department and FBI agents, acting on a whistleblower’s allegations, served a criminal search warrant on Alaska Airlines, seeking evidence of maintenance irregularities.


The investigation expanded to include the January 2000 crash of Alaska Flight 261 that killed 88 people, which the National Transportation Safety Board later blamed on the airline’s faulty maintenance practices and poor FAA oversight.

But no criminal charges were filed, although the FAA, in a separate administrative review, ultimately found that Alaska and three of its managers had violated safety regulations, fining the carrier $44,000, revoking the mechanic licenses of two of the managers and suspending the license of the third.

Federal criminal charges were brought over the May 11, 1996, ValuJet Flight 592 crash that took off from Miami International Airport and plunged into the Everglades minutes later, killing 110 people.

Federal prosecutors in Florida filed a 24-count indictment against SabreTech, an airline maintenance contractor, and its workers over alleged violations in the handling of oxygen containers blamed for the crash. SabreTech was found guilty on nine counts but was acquitted on conspiracy charges, according to news reports. An appeals court later overturned all but one of the counts, the improper training of employees.

One issue that has arisen in criminal investigations of safety matters is whether they deter people from cooperating in other government investigations and civil proceedings.

In 2000, the National Transportation Safety Board warned that its findings on the cause of the 1999 deadly pipeline explosion in Bellingham could be indefinitely delayed because of a separate criminal investigation that had silenced key witnesses.


Then-NTSB Chairman Jim Hall said his agency had yet to question eight computer-room operators at Olympic Pipe Line who invoked their Fifth Amendment right against self-incrimination shortly after the June 10 blast that killed two boys and led to the death of a young man.

Eric Weiss, an NTSB spokesman, said he couldn’t comment on whether any individuals have declined to provide information on the Boeing 737 MAX crashes in light of the criminal investigation.