A Greenberg Traurig lobbyist is at the center of a U.S. senator’s investigation into how "political intelligence" can affect markets. The inquiry includes an examination of the lobbyist’s email about a dramatic change in government’s health care policy more than an hour before it was announced.

Senator Chuck Grassley (R-Iowa) is seeking all of Greenberg Traurig’s internal and external communication about the April 1 announcement by the Centers for Medicare and Medicaid Services dealing with proposed rate cuts, according to a letter Grassley wrote this month to the law firm’s outside counsel.