While some smaller local courts have experimented with trials using videoconferencing tools such as Zoom, criminal trials generally can’t be done remotely unless a defendant agrees. That is because criminal defendants have a right under the Constitution to confront witnesses against them, which usually entails face-to-face confrontation, said George Fisher, a professor at Stanford Law School.

Some attorneys worry the near-term makeup of juries could be meaningfully different if many people are excused from immediate service due to concerns about the virus. Juries might not have as many older members, for instance, since the consequences of infection tend to be more serious for senior citizens, Mr. Fisher said.

There also could be a correlation between people’s openness to serving on Covid-19-era juries and their political leanings, said Mr. Fisher, who was earlier a prosecutor in Massachusetts. Democrats are more likely to believe the dangers of coronavirus remain significant, while Republicans tend to say the virus’ worst impacts are in the past, according to a Pew Research Center poll released in June.

“If I were a judge hearing all of this, I would say it is much too speculative to assume the pandemic will skew jurors toward one side or another, and the gears of justice have to keep moving,” he said.