Lawyer Charles J. Cooper has spent his career as a leading conservative warrior in constitutional law, from his time heading the Justice Department’s Office of Legal Counsel under President Ronald Reagan to his longtime representation of the National Rifle Association to his 2013 Supreme Court argument against the right to same-sex marriage.

He is also a longtime acquaintance of Merrick Garland, President Obama’s nominee to the Supreme Court, and Cooper weighed in on Garland’s behalf at a key juncture two decades ago when Garland was nominated to the U.S. Court of Appeals by President Bill Clinton.

“Like our respective bosses, Merrick and I disagreed on many legal issues,” Cooper wrote in a 1995 letter to the Senate Judiciary Committee, referring to the time they spent together as Supreme Court clerks in the late 1970s — Cooper for the conservative justice William Rehnquist and Garland for liberal William Brennan. “Still, I believe that Merrick possesses the qualities of a fine judge.”

“Not only is Merrick enormously gifted intellectually, but he is thoughtful as well, for he respects other points of view and fairly and honestly assesses the merits of all sides of an issue,” Cooper continued. “And he has a stable, even-tempered, and courteous manner. He would comport himself on the bench with dignity and fairness. In short, I believe that Merrick Garland will be among President Clinton’s very best judicial appointments.”

Garland was eventually confirmed to that court after a two-year confirmation battle.

Now Garland is facing an even more difficult path to confirmation, and since he was nominated to the high court earlier this month, several noted conservative lawyers have spoken up on Garland’s behalf. They include Miguel Estrada, a former Justice Department official who was the subject of a pitched and ultimately unsuccessful confirmation battle for the U.S. Court of Appeals; Kenneth Starr, the former solicitor general and Clinton-era independent counsel who is now president of Baylor University; Richard Painter, who was associate counsel to President George W. Bush; and Michael Chertoff, the former federal judge who served as homeland-security secretary under Bush.

Cooper is joining in the praise — to a point. In an email Sunday, he said his “high opinion of Judge Garland has not changed — indeed, it has only strengthened — over the course of the 19 years since I wrote these words.”

“The qualities that I saw in Merrick Garland as a nominee to the D.C. Circuit have been displayed in abundance by Judge Garland as a member of that court,” he wrote.

But Cooper’s praise for Garland comes with this caveat — he supports the decision of the Senate Republican leadership to withhold action on his Supreme Court nomination: “Given that the vacancy occurred at a time when the presidential election process was well underway, I believe it entirely within the Senate’s constitutional power to defer action on the vacancy until a new president is inaugurated in January 2017.”

That position might not offer significant new ammunition to Democratic supporters of Garland who are pressing for a confirmation hearing. But if the politics of the nomination were to change — most obviously, if Hillary Clinton or Sen. Bernie Sanders were elected in November to succeed Obama — the support of a prominent conservative jurist such as Cooper helps demonstrate that Republicans would be hard-pressed to demand a more acceptable nominee from a Democratic president.