There has not been a constitutional convention since the original in Philadelphia. A 2016 report from the Congressional Research Service discusses the process of calling a convention, as well as the questions and uncertainties surrounding that process. In the 1990s, the issue came up in the context of a balanced budget amendment.
Phoebe Petrovic at Pro Publica:
A behind-the-scenes legal effort to force Congress to call a convention to amend the Constitution could end up helping President Donald Trump in his push to expand presidential power.
While the convention effort is focused on the national debt, legal experts say it could open the door to other changes, such as limiting who can be a U.S. citizen, allowing the president to overrule Congress’ spending decisions or even making it legal for Trump to run for a third term.
Wisconsin Watch and ProPublica have obtained a draft version of a proposed lawsuit being floated to attorneys general in several states, revealing new details about who’s involved and their efforts to advance legal arguments that liberal and conservative legal scholars alike have criticized, calling them “wild,” “completely illegitimate” and “deeply flawed.”
The endeavor predates Trump’s second term but carries new weight as several members of Trump’s inner circle and House Speaker Mike Johnson have previously expressed support for a convention to limit federal government spending and power.
Article V of the Constitution requires Congress to call a convention to propose and pass amendments if two-thirds of states, or 34, request one. This type of convention has never happened in U.S. history, and a decadeslong effort to advance a so-called balanced budget amendment, which would prohibit the government from running a deficit, has stalled at 28.
Despite that, the lawsuit being circulated claims that Congress must hold a convention now because the states reached the two-thirds threshold in 1979. To get there, these activists count various calls for a convention dating back to the late 1700s. Wisconsin’s petition, for example, was written in 1929 and was an effort to repeal Prohibition. The oldest petition they cite, from New York, predates the Bill of Rights. Some others came on the eve of the Civil War.