Kevin Quinn cited in The New York Times, Five Thirty Eight, March 29, 2012
The method, called the Martin-Quinn Scores for the two scholars that developed it, Andrew D. Martin of the Washington University School of Law and Kevin M. Quinn of the Berkeley School of Law, estimates the court’s ideology by evaluating the combinations in which different justices vote with one another and how this changes over time…. The Martin-Quinn method suggests that there has been some overall rightward drift among almost all members of the court, including the more liberal justices, since Chief Justice Roberts took over for Chief Justice William H. Rehnquist.