More than 200 lawyers have formed a new legal advocacy group challenging what they call the erosion of the rule of law under the presidency of Donald Trump.

“We, as lawyers, cannot ignore or remain silent about President Donald Trump's disregard of these core values and principles. We must speak out,” the lawyers wrote in an open letter that was distributed Thursday.

The new group, called Lawyers Defending American Democracy, bills itself as nonpartisan. The signers of the open letter include numerous Big Law partners across the country, law professors, former federal and state judges, and others. The group is led by Scott Harshbarger, a former Massachusetts state attorney general and now senior counsel in Boston at Casner & Edwards.

Among the lawyers who signed the letter: Jon Bouker, co-leader of the government relations practice at Arent Fox; Stanley McDermott III, a DLA Piper partner in New York; Robert Dell, retired global chair of Latham & Watkins; Emanuel Rouvelas, a partner at K&L Gates in Washington; William Meserve, a retired Ropes & Gray partner; retired Covington & Burling partner Jonathan Blake; Hogan Lovells senior counsel Kathy Weinman in Boston; Stanley Twardy Jr., a Day Pitney partner in Connecticut; and Robert Skinner, a Ropes & Gray partner in Boston. Robert Saudek in Atlanta, a retired managing partner of Morris, Manning & Martin, also signed the letter, as did Ralph Levy, a retired King & Spalding partner in Atlanta.

Donald Stern, a managing director at the compliance monitoring firm Affiliated Monitors Inc. and a former U.S. attorney for Massachusetts, also signed the letter. Among the former judges were: A. Howard Matz, who served on the Los Angeles trial bench and who's now senior counsel at Bird Marella; and Eric Younger, who served on the California Superior Court in Los Angeles.

Atop the list of signatories is a disclaimer that states: “Organizational affiliation is listed solely for identification purposes. Our views are not attributable to any organization with which we may be affiliated.”

The group paints itself as nonpartisan and focused on defending “fundamental principles and norms of American democracy,” such as an independent press and the expectation of honesty from public officials. The group urged Trump to “respect and honor” the independence of the federal judiciary and law enforcement, parts of government he has been known to publicly pressure through tweets and other means.

Trump has faced criticism over his remarks about judges and court rulings. In November, delivering a rare public rebuke, Chief Justice John Roberts Jr. said in a response to remarks from Trump: “We do not have Obama judges or Trump judges, Bush judges or Clinton judges. What we have is an extraordinary group of dedicated judges doing their level best to do equal right to those appearing before them. That independent judiciary is something we should all be thankful for.”

The new legal group isn't the first to materialize in opposition to some of the statements and positions of the Trump administration. Last November, a new conservative lawyers' group called Checks and Balances emerged. The group's mission statement also spoke about upholding the rule of law, and addressed “the power of truth.”

There can be professional risks for lawyers attaching their names to letters that are adverse to the Trump administration.

The U.S. Commerce Department last year rescinded its offer to Covington partner Peter Lichtenbaum to serve in a highly visible compliance monitor role after learning he was among the lawyers and former government officials who'd signed a “Never Trump” letter in the run-up to the 2016 presidential election. Secretary Wilbur Ross gave the ZTE Corp. monitorship to Barnes & Thornburg partner Roscoe Howard, a former U.S. attorney in Washington, D.C.

A lawyer who had followed the Commerce Department's decision to rescind the offer to Lichtenbaum told the NLJ recently that the move “on its face is a clear violation of the First Amendment.” The agency declined to comment.