Judge Timothy M. Tymkovich of Colorado has announced his intent to step aside as an active member of the Denver-based federal appeals court, creating the first vacancy for President Donald Trump to fill in his second term.

In a Feb. 24 letter to Trump and various members of the federal judiciary, Tymkovich indicated he will take a form of semi-retirement known as “senior status,” in which judges may take on a reduced caseload based upon their years of service and their age. The senior status will take effect upon confirmation of his successor.

Tymkovich is a George W. Bush appointee to the U.S. Court of Appeals for the 10th Circuit, which hears appeals in federal cases arising from Colorado, Oklahoma, Kansas, Utah, New Mexico, and Wyoming. It has 12 presidentially nominated, U.S. Senate-confirmed judges, including two appointed by Trump in his first term.

The 10th Circuit also has a handful of senior judges, the most recent of whom to take senior status was Mary Beck Briscoe of Kansas in 2021.

Tymkovich joins two other Bush-appointed federal judges who indicated they will also take senior status in recent days: Chief Judge Jeffrey S. Sutton of the Cincinnati-based Sixth Circuit and Chief Judge Debra Ann Livingston of the New York City-based Second Circuit. Tymkovich, who joined the 10th Circuit in 2003, served as its chief judge between 2015 and 2022.

Tymkovich’s tenure “has been marked by both doctrinal clarity and institutional influence. As with any long-serving appellate judge, some of his holdings have been debated in the academy and by practitioners, but his impact on the development of law in the 10th Circuit — both as a decision-maker and as a mentor to law clerks and younger jurists — is undeniable,” said attorney Katayoun A. Donnelly, who practices before the 10th Circuit. “His legacy is that of a disciplined jurist who contributed to the coherence and reputation of his court. He also is a genuinely kind and gracious man.”

“Judge Tymkovich was also a skilled leader, and as chief judge, he led the court through the unprecedented COVID pandemic,” added Adam Mueller, who also practices before the 10th Circuit. “Finally, and on a personal note, Judge Tymkovich is an extraordinarily decent man. I served as a law clerk in the same courthouse but for a different judge, and Judge Tymkovich was always gracious and kind. And I will always enjoy the memories of the weekend of skiing he and his law clerks spent with my judge and co-clerks in Beaver Creek.”

Tymkovich attended Colorado College and graduated from the University of Colorado’s law school. He has been involved for decades with the Federalist Society, which is a cornerstone of the conservative legal movement.

After clerking for Colorado Supreme Court Chief Justice William H. Erickson, he entered private practice. Later, he campaigned for Gale Norton, who became Colorado’s attorney general in 1991. As Norton’s solicitor general, Tymkovich unsuccessfully defended Amendment 2 before the U.S. Supreme Court, which voters enacted in 1992 to ban the state and local governments from establishing protections for gay, lesbian, and bisexual people.

After re-entering private practice, Bush nominated Tymkovich to the 10th Circuit in 2001. As Tymkovich recalled on the 10th Circuit Historical Society’s podcast in October, his nomination stalled once Democrats gained a majority in the Senate midway through 2001.

Since becoming a judge, Tymkovich has authored multiple opinions in high-profile cases, including those that have reached the Supreme Court. For example, Tymkovich authored a dissent in 303 Creative v. Elenis, in which a Christian web designer asserted her First Amendment right to decline to create websites for same-sex weddings, notwithstanding Colorado’s non-discrimination law. Tymkovich’s dissent featured prominently in the Supreme Court’s 2023 majority opinion, authored by his friend and former 10th Circuit colleague, Justice Neil M. Gorsuch.

“We both liked to ski, so we did some skiing together. And some hiking. Really, he was my best friend on the court when he got settled in here,” Tymkovich said of Gorsuch on the podcast.

Tymkovich was also on a list of potential Supreme Court nominees that Trump disclosed during his first term.

Several of his former clerks have moved on to prominent positions in conservative political and legal circles, including U.S. Rep. Jeff Hurd, Ninth Circuit Judge Patrick J. Bumatay, and Colorado solicitor general-turned U.S. District Court Judge Daniel D. Domenico.

“I was incredibly fortunate he hired me as a clerk when he first joined the bench, and even luckier to have him as a role model and mentor ever since,” Domenico told Colorado Politics. “His example is impossible to live up to, but I think all of us former clerks are better people and lawyers for the time we spent with him. I am pleased he will continue to serve as a senior judge and selfishly hope he does so for another couple of decades.”

Since joining the bench, Tymkovich has repeatedly visited his ancestral home of Ukraine, in part to meet with judges and discuss the rule of law. In 2024, he was one of 14 federal judges who visited Israel to meet with Supreme Court justices, academics, government officials, and others.

Last year, Tymkovich testified before a congressional subcommittee in favor of the JUDGES Act, which would establish dozens of trial court judgeships over several years across the federal judiciary, including two more seats on Colorado’s district court.

In addition to his work on the 10th Circuit, Chief Justice John G. Roberts Jr. assigned Tymkovich to sit on the nation’s foreign surveillance appeals court. Tymkovich has also visited other circuit courts to hear appeals and has occasionally handled cases in the trial courts. On the historical society’s podcast, he said the biggest challenges during his seven years as chief judge included the expansion of federal jurisdiction over certain criminal cases in Oklahoma and dealing with the COVID-19 pandemic.

“Fifty-fifty hindsight, maybe there were some things I would do differently. But for the most part, it forced the court to embrace technology,” he said. “We enhanced all the technology in our courtrooms so we could have remote oral arguments. It allowed judges who were less comfortable coming to Denver (to) participate by Zoom so they didn’t have to travel, and we could have hybrid arguments because of that.”

Potential successors for Tymkovich include Domenico, First Assistant U.S. Attorney J. Bishop Grewell and William E. Trachman, general counsel for the Mountain States Legal Foundation.

“It is safe to assume that the new judge will be a conservative jurist that Trump believes will, above all, loyally support Trump’s policies and the practices of the administration,” said attorney Darold W. Killmer, who practices in Colorado’s federal courts.

Currently, the 10th Circuit has one other Bush-appointed judge eligible to take senior status: Judge Harris L Hartz of New Mexico. Chief Judge Jerome A. Holmes of Oklahoma will be eligible for senior status when he turns 65 later this year, but his seven-year term leading the circuit will not expire until October 2029.