Will John Roberts constrain Trump?

But many other analysts say that, in practice, Republican appointees on the courts—particularly the Supreme Court—have already shown enormous deference to Trump’s claims of expansive authority. In 2018, the five Republican-appointed Supreme Court justices outvoted the others to uphold Trump’s ban on travel from mostly Muslim nations, for example. In more recent questioning, the same coalition appeared poised to allow Trump to end President Barack Obama’s Deferred Action for Childhood Arrivals program, which sheltered from deportation young people brought to the country illegally by their parents.

The biggest departure to this pattern of deference from the Court’s GOP majority came in June, when Roberts joined with the four Democratic appointees to block the administration’s effort to add a citizenship question to the 2020 census, which critics feared would depress minority participation.

Trump’s boundless instinct to press presidential boundaries virtually ensures that the Supreme Court will continue to face a steady flow of cases testing his claims. It already is facing cases involving Trump’s efforts to prevent both congressional investigators and New York criminal investigators from obtaining his tax returns, and his claims of “absolute immunity” from congressional testimony for current and former close aides appear headed toward the Court, too.

All this means that whether Trump stays in office for one more year or five, one of the key variables will be whether Roberts’s ruling in the census case was an exception or a signal of his determination to limit presidential authority.