Put forward:
...we've identified one reasonably objective and quantifiable measure of a judge's activism, and we've used it to assess the records of the justices on the current Supreme Court.
Here is the question we asked: How often has each justice voted to strike down a law passed by Congress?
Sounds good, to me. It's certainly a better definition for activist judge than the one right-wingers use, ie: a jurist whose rulings dissatisfy me.
Declaring an act of Congress unconstitutional is the boldest thing a judge can do. That's because Congress, as an elected legislative body representing the entire nation, makes decisions that can be presumed to possess a high degree of democratic legitimacy. In an 1867 decision, the Supreme Court itself described striking down Congressional legislation as an act "of great delicacy, and only to be performed where the repugnancy is clear."
Ok, got it. When a judge overrules the will of people, as expressed through their votes (cough, Bush v. Gore, cough) or their representatives that's activism. Understood.
Since the Supreme Court assumed its current composition in 1994, by our count it has upheld or struck down 64 Congressional provisions. That legislation has concerned Social Security, church and state, and campaign finance, among many other issues. We examined the court's decisions in these cases and looked at how each justice voted, regardless of whether he or she concurred with the majority or dissented.
Ok, getting a little bored here. Open the envelope and tell us who it was, already!
We found that justices vary widely in their inclination to strike down Congressional laws. Justice Clarence Thomas, appointed by President George H. W. Bush, was the most inclined, voting to invalidate 65.63 percent of those laws; Justice Stephen Breyer, appointed by President Bill Clinton, was the least, voting to invalidate 28.13 percent. The tally for all the justices appears below.
Thomas 65.63%
Kennedy 64.06%
Scalia 56.25%
Rehnquist 46.88%
O’Connor 46.77%
Souter 42.19%
Stevens 39.34%
Ginsburg 39.06%
Breyer 28.13%