Pro-business and criminal defense advocacy groups are accusing the Department of Justice of overreaching its subpoena power by using an aggressive new tactic to retrieve foreign documents for use in criminal antitrust proceedings.

Historically, foreign documents fall outside the scope of grand jury subpoenas, but the Justice Department is arguing that those documents are fair game once they enter the United States. The matter is expected to ultimately make its way to the U.S. Supreme Court.

“This is the first time I can recall that the Justice Department issued subpoenas to the law firm of a party as a way of ...