Chief Justice John G. Roberts Jr., left, shown with Justice Anthony M. Kennedy at President Obama’s State of the Union address in January 2015, steered clear of controversy in his year-end report. (Mandel Ngan/AFP)

The federal courts in general and the Supreme Court in particular have been a focal point of the contentious 2016 election campaign, but Chief Justice John G. Roberts Jr. continued to steer well clear of controversy in his year-end report issued Saturday.

Roberts did not mention that the court has been shorthanded since the death of Justice Antonin Scalia in February nor the Republican-controlled Senate’s refusal to hold a hearing for President Obama’s nominee to the court, U.S. Circuit Court Judge Merrick Garland.

That action kept the seat open for an appointment by President-elect Donald Trump, and will retain a conservative majority of Republican nominees on the Supreme Court.

Instead, Roberts used his Year-End Report on the Federal Judiciary to focus on what he said was the underappreciated role of federal district judges, who conduct trials and serve at the first level of the justice system.

“While the Supreme Court is often the focus of public attention, our system of justice depends fundamentally on the skill, hard work, and dedication of those outside the limelight,” Roberts wrote.

Trump has the chance to fill an uncommon number of vacancies in the federal courts in addition to the open Supreme Court seat, giving him a monumental opportunity to reshape the judiciary after taking office.

The estimated 103 judicial vacancies that Obama is expected to hand over to Trump in the Jan. 20 transition of power is nearly double the 54 openings Obama found eight years ago following George W. Bush’s presidency.

There already are 84 vacancies at the district level Roberts was writing about, with about another dozen openings expected early in the year.

There are 673 district judgeships authored by Congress around the nation, and Roberts said they are aided by more than 500 senior district judges, who are eligible for retirement with full pay but still continue to work part time.

“Unlike politicians, they work largely outside of the public eye,” Roberts wrote. The typical judge has a docket of about 500 cases, he said, and is responsible for all aspects of moving a lawsuit toward resolution.

“The judge must have mastery of the complex rules of procedure and evidence and be able to apply those rules to the nuances of a unique controversy,” he wrote. “As the singular authority on the bench, he must respond to every detail of an unscripted proceeding, tempering firm and decisive judgment with objectivity, insight, and compassion. This is no job for impulsive, timid, or inattentive souls.”

The most challenging part of the job is sentencing those found guilty of a criminal offense, Roberts wrote, balancing the perspectives of prosecutor, defendant and victim and guided by legislative directive and sentencing guidelines.

“At the end of the day, the sentence nonetheless critically reflects the judge’s wisdom, experience, and educated grasp of what he observed firsthand in the courtroom,” Roberts wrote. “In delivering the sentence, the judge speaks as the voice of the community.”

Despite the encomium from Roberts, district judges are a rarity at the Supreme Court. Although they often rise to the regional appellate courts, only Justice Sonia Sotomayor on the current Supreme Court served as a district judge.

She often references her experiences running a courtroom and sentencing defendants in exchanges with her colleagues. She has said that if she ever left the high court and continued to hear cases in retirement, she would like to return to the district court, rather than serve on appeals courts as other retired justices have done.

District judges are constrained in their interpretation of the law not only by Supreme Court precedent but also the decisions of the circuits in which they are based. But their power has been shown recently when conservative states have challenged Obama administrative actions.

Three judges, all in Texas, have issued nationwide injunctions stopping administration proposals regarding deportation policies, accommodations for transgender students in public schools and overtime rules.