Tom Goldstein offers a quick analysis of the four liberal justices, four conservative justices, and Justice Kennedy.
I also considered the 10 cases I consider most significant. Of those, the left prevailed in 8. Those included the first 7 of the Term. (I mention the early cases to give a sense of how the results must have appeared inside the Court as the Term went along.) The right prevailed in 2, both in the final sitting of the Term.
In the 10, no Justice on the left voted with the right; the four Justices on the left voted together in every one of those cases. A Justice on the right voted with the left 4 times. Those votes determined the outcome in 2 cases, because Justice Kennedy voted for the more conservative result.
Note that the analysis above is skewed against finding the Term particularly liberal by treating Justice Kennedy as the Court’s “center.” That is true ideologically, but he is certainly a conservative. If he were characterized that way for my analysis, the number of defections to the left would be much higher.
By that measure, a Justice on the right voted with the left 25 times (compared with 3 times the reverse happened). That occurred in all 10 of the 10 major cases (because no Justice on the left voted with the right in any of those cases), and determined the outcome in all of them.