At the federal courthouse in Washington, a woman called the chambers of the judge assigned to the election interference case against former President Donald J. Trump and said that if Mr. Trump were not re-elected next year, “we are coming to kill you.”
At the Federal Bureau of Investigation, agents have reported concerns about harassment and threats being directed at their families amid intensifying anger among Trump supporters about what they consider to be the weaponization of the Justice Department. “Their children didn’t sign up for this,” a senior F.B.I. supervisor recently testified to Congress.
And the top prosecutors on the four criminal cases against Mr. Trump — two brought by the Justice Department and one each in Georgia and New York — now require round-the-clock protection.
As the prosecutions of Mr. Trump have accelerated, so too have threats against law enforcement authorities, judges, elected officials and others. The threats, in turn, are prompting protective measures, a legal effort to curb his angry and sometimes incendiary public statements, and renewed concern about the potential for an election campaign in which Mr. Trump has promised “retribution” to produce violence.
Given the attack on the Capitol by Trump supporters on Jan. 6, 2021, scholars, security experts, law enforcement officials and others are increasingly warning about the potential for lone-wolf attacks or riots by angry or troubled Americans who have taken in the heated rhetoric.
In April, before federal prosecutors indicted Mr. Trump, one survey showed that 4.5 percent of American adults agreed with the idea that the use of force was “justified to restore Donald Trump to the presidency.” Just two months later, after the first federal indictment of Mr. Trump, that figure surged to 7 percent.