The Supreme Court heard two cases challenging laws in Washington and Colorado that require members of the Electoral College in every quadrennial presidential election to cast their ballots in favor of the winner of that state’s popular votes.

Some justices expressed concern during oral arguments on May 13 that not requiring electors to vote in accordance with the wishes of popular voters in their state could lead to political upheaval and debilitating chaos.

The hearing comes as the next presidential election approaches on Nov. 3. In the 2016 election, Republican Donald Trump won a majority of electoral votes and became president, defeating Democrat Hillary Clinton, who won more popular votes.

That event appeared to give a boost to the National Popular Vote movement, an effort to create an interstate compact compelling presidential electors to cast their ballots for the candidate who wins the popular vote nationwide. The goal of the movement is to effectively mandate the direct election of the president without having to amend the U.S. Constitution, a notoriously difficult task.

Click here for the full article