From The Huffington Post:

“Part of what Congress does is take the easy way out; there’s a laziness factor to just let the executive do something,” said Kevin Kosar, vice president for policy at the R Street Institute, a libertarian think tank. “Part of it is also a quasi-parliamentary mentality that our legislature has fallen into. If there’s a Republican president, you wave the Republican flag. If the president is a Democrat, and you’re a Republican, you’re supposed to be reflexively against that person.”