US Senate Majority Leader Chuck Schumer (D-N.Y.) proposed on Thursday a bill called the "No Kings Act," which would reassert that presidents have no prosecutorial immunity for criminal acts and reverse a precedent established by the Supreme Court last month.
SCOTUS ruled in Trump v. United States that all presidents have "absolute immunity from criminal prosecution for actions within his conclusive and preclusive constitutional authority" and "at least presumptive immunity" for official acts but "no immunity for unofficial acts."
The SCOTUS ruling was not based on legal precedent or thoughtful debate between conservative and liberal justices but rather an explicit attempt to shield future far-right presidents. Given the court's super-majority of pro-Trump justices, coupled with its current status of lifetime terms and lack of an ethics code, the only way to reign in their power and that of their friends in government is to codify a new law banning such ludicrous legal theories.
The Democrats are projecting their nefarious goals with respect to SCOTUS onto the Republican Party. The court's ruling was a very mild one that simply asserted the right of presidents — and not just Trump, but all presidents from either party — to govern without fear of being prosecuted by their opponents after leaving office. The Democrats don't want to reform the court—they want to completely redesign it.