Associated Press

In the last two days, the U.S. Supreme Court delivered two historic rulings. The first upheld a major component of Obamacare. The second legalized same-sex marriage on a national level. Both issues divided the court—the first ruling was 6-3 and the second was 5-4.

One Supreme Court Justice in particular has played a pivotal role in influencing these decisions: Justice Anthony Kennedy. In the graphic below, the current justices are scored on a one-dimensional scale from liberal to conservative, where positive values are conservative and negative values liberal. As the graphic shows, four of the court’s justices are solidly conservative and four are solidly liberal. While Kennedy started out fairly conservative (his score peaked at 1.4), he has gradually transitioned to a more liberal ideology. His current score of 0.5 indicates that he is essentially neutral on average, making him the all-important swing vote.

Supreme Court Justices Ideology Over Time | InsideGov

Justice Kennedy’s evolving philosophy is mirrored by the court’s own transition toward more liberal rulings. From the 1980s through the early 2000s, the Supreme Court tended to vote more conservatively. But that trend has disappeared in the last few years. In fact, 55% of the court’s rulings were liberal in 2013.

Supreme Court Decision Ideology | InsideGov

With these two new rulings, SCOTUS is continuing to assert a more liberal ideology. Has the Supreme Court reached a tipping point?