This is the time of year that the news media rolls out a familiar graphic: nine head shots of Supreme Court justices, arrayed from most liberal to most conservative.

In spacing the head shots at equal intervals, the graphics suggest a steady procession from left to right. But the reality is a series of clusters, a few loners and several telling gaps.

There is no dispute that the court has a four-member liberal wing and a four-member conservative wing, with Justice Anthony Kennedy somewhere in the middle.

But not every liberal is liberal in the same measure. In the term that ended in June 2013, the three women on the court — Justices Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan — were tightly bunched on the left side of the array. They cast liberal votes around 70 percent of the time. Justice Stephen Breyer was substantially more conservative, casting liberal votes 59 percent of the time.