[Dow Jones/WSJ paywall] via Morningstar: “Federal prosecutors and Department of Transportation officials are scrutinizing the development of Boeing Co.’s 737 MAX jetliners, according to people familiar with the matter, unusual inquiries that come amid probes of regulators’ safety approvals of the new plane. A grand jury in Washington, D.C., issued a broad subpoena dated March 11 to at least one person involved in the 737 MAX’s development, seeking related documents, including correspondence, emails and other messages, one of these people said. The subpoena, with a prosecutor from the Justice Department’s criminal division listed as a contact, sought documents to be handed over later this month. It wasn’t immediately clear whether the Justice Department’s probe is related to scrutiny of the Federal Aviation Administration by the DOT inspector general’s office, reported earlier Sunday by The Wall Street Journal and that focuses on a safety system that has been implicated in the Oct. 29 Lion Air crash that killed 189 people, according to a government official briefed on its status. Aviation authorities are looking into whether the anti-stall system may have played a role in last week’s Ethiopian Airlines crash, which killed all 157 people on board.

The subpoena was sent a day after the Ethiopian Airlines crash a week ago. Representatives of the DOT’s inspector general and the Justice Department declined to comment. The inspector general’s inquiry focuses on ensuring relevant documents and computer files are retained, according to the government official familiar with the matter…”