With the Rolling Stones playing a few special concerts this winter with walk-on appearances by Bill Wyman, Twitter is abuzz with the factoid that the Rolling Stones are now older, on average, than the US Supreme Court.

Does this claim hold water? It does. I calculated the age of each institution at the end of each calendar year from 1962 to the present. The US Supreme Court is older now than at any time from 1962 to 1978, but for the last 60 years it has nearly always been between 60 and 70. The peak is in 1985 thanks to Brennan, Marshall, Burger, Blackmun and Powell all being over 76, and the low point is also the Stones’ low point, 1962, when the oldest justice was Warren at 71. A local minimum was reached in 1994 with Blackmun’s replacement by Breyer, the sixth new justice in a decade.

In contrast to the stable age profile of the Supreme  Court, the Rolling Stones have increased in age nearly every year from 1962 to the present. My system for determining who is and is not a Rolling Stone is fairly stringent, with everyone who may be considered to have “joined” the Stones since 1975 being better described as a sideman. As such, Stones personnel changes have been as follows:

1963 – pianist Ian Stewart (25) demoted to roadie/sideman
1969 – death of guitarist Brian Jones (27), replacement by Mick Taylor (20)
1974 – departure of Taylor (25)
1975 – addition of guitarist Ronnie Wood (28)
1992 – departure of bassist Bill Wyman (56)

Based on my statistics, the Rolling Stones are now older than the Supreme Court, but this is not a new phenomenon, as the Stones have comprised the same four individuals for years, while the last change to the US Supreme Court was the replacement of John Paul Stevens by the 40-years-younger Elena Kagan on August 7, 2010. With Kagan’s appointment, the Supremes averaged 64.4 years of age at the end of 2010, while the Stones averaged 66.5. They have each aged since then at a rate of 1 year per year, as seen in the parallel trajectories in the above graph.

However, there has long been some “wiggle room” in determining which individuals can be considered Rolling Stones. In 1993 the band appointed a new bassist, Darryl Jones (born 1961). If Jones were considered a true replacement for Wyman, the band’s mean age would at this point drop substabtially and even as of mid-2012 would be lower than that of the Supreme Court. To my mind this is a fallacious notion. Despite his consistent role in Stones performances since then, Jones is described by Wikipedia as a “salaried employee”, who is largely anonymous onstage, does not receive an equal share of touring proceeds, and appears to fulfill a “sideman” role similar to that of the keyboard guy and the saxophone guy.

If Jones is to be considered a Rolling Stone, in recognition of his years of devoted service, we can then say that on November 25th, 2012 the Stones finally became older than the Supreme Court, with the return of Bill Wyman (age 76) for “It’s Only Rock n’ Roll (But I Like It)” during their set at London’s O2 Arena. However, it follows that during any future concerts at which Wyman is not present, the band’s age will again drop to below that of the Supreme Court. This state of uncertainty is suboptimal and we hope the recent results from CERN, which seem likely to deal a death blow to supersymmetric string theory, also resolve the issue of whether the Rolling Stones contain one, two, or (as I conclude) zero bassists.