NEW YORK Conservative former U.S. appeals court judge J. Michael Luttig in an opinion piece on Sunday said Republicans are making a serious error with "spineless support" for Donald Trump's new bid for the White House.

Lutting wrote in the New York Times that the Republican Party is in part to blame for the former president's federal indictment earlier this month accusing Trump of mishandling classified documents. There are few signs that Trump will face political consequences internally, which undermines rule of law and threatens the future of the party, Luttig said.

"Building the Republican campaign around the newly indicted front-runner is a colossal political miscalculation, as comedic as it is tragic for the country," said Luttig, an appointee of Republican President George H.W. Bush who served from 1991 to 2006.

"No assemblage of politicians except the Republicans would ever conceive of running for the American presidency by running against the Constitution and the rule of law. But that’s exactly what they’re planning."

Luttig served as an informal adviser to Trump's vice president, Mike Pence, and gave testimony a year ago to the congressional committee that investigated the Jan. 6, 2021, attack on the U.S. Capitol.

Since federal prosecutors unsealed a 37-count indictment against Trump earlier this month, most candidates in the crowded Republican primary field have come to his defense. Some have said as president they would pardon Trump, should he be convicted in the case.

Polling shows Trump holding a strong lead over his Republican rivals.

(Reporting by Tyler Clifford; Editing by Scott Malone and Chizu Nomiyama)