This is the provocative question addressed by co-authors Professor David Stras (a colleague of mine at Minnesota) and Ryan Scott (a former student of mine, now clerking for Judge Michael McConnell). It is available here. While I'm not entirely on board for their analysis, attention should be paid to these two rising young stars of the legal academy, who've been specializing lately in institutional reform proposals for the federal courts.
Here's a summary from the authors:
With burgeoning caseloads and persistent vacancies in many federal courts, senior judges play a vital role in the continued well-being of our federal judiciary. Despite the importance of their participation in the judicial process, however, senior judges raise a host of constitutional concerns that have escaped the notice of scholars and courts. Many of the problems originate with recent changes to the statute authorizing federal judges to elect senior status, including a 1989 law that permits senior judges to fulfill their statutory responsibilities by performing entirely nonjudicial work. Others arise from the ambiguity of the statutory scheme itself, which seems to suggest that senior status represents a separate constitutional office, requiring reappointment, even though senior judges nominally “retain” judicial office under federal law.
In the first scholarly article addressing the constitutionality of senior judges, the authors examine two general constitutional objections: (1) whether the requirement that senior judges be designated and assigned by another federal judge before performing any judicial work violates the tenure protection of Article III; and (2) whether allowing judges to elect senior status, without a second intervening appointment, violates the Appointments Clause. They also examine whether two specific types of senior judges - the “bureaucratic senior judge” who performs only administrative duties and the “itinerant senior judge” who sits exclusively on courts outside his home district or circuit - violate the Constitution.
The authors conclude that the current statute authorizing senior judges raises serious constitutional problems that should be addressed by Congress or the Judicial Conference of the United States. In that respect, they formulate a number of straightforward suggestions to repair senior status without having to sacrifice any of the considerable benefits that senior judges have conferred on the federal judiciary over the years.