These political scientists may have just discovered why U.S. politics are a disaster

There's a lot of disgust in America with politicians' inability to get things done. In the race to win the Republican presidential nomination, that disgust has so far benefited outsider candidates. Non-career politicians Donald Trump, Carly Fiorina and Ben Carson have all promised to ride in and fix Washington.

But new research by Nolan McCarty, a professor at Princeton University, and other political scientists suggests this disgust — and America's political dysfunction — won't be that easy to fix. Working with political scientist Boris Shor and economist John Voorheis, McCarty...