Senate Democrats are examining the Justice Department’s subpoenas of New York Times reporters who covered security concerns involving President Trump’s Qatar-donated Air Force One aircraft. The inquiry matters because compelling journalists to identify confidential sources can affect press freedom, while the department says it is investigating potential leaks of classified information.

The subpoenas sought grand-jury testimony and, in some instances, communications records connected to the reporters’ sources. Democrats questioned whether prosecutors had followed rules requiring such steps to be a last resort; the Justice Department maintained that the reporters were witnesses rather than targets of its investigation.