Thoughts on a recess appointment
I see the idea being debated of Obama making a recess appointment to replace Justice Scalia. (The last recess appointment to the Court was that of Justice Brennan, in 1956... motivated, interestingly enough, by an upcoming presidential race).
Such a move would have to be made in haste (the Senate is in recess for just over another week, and is unlikely to allow another recess after that).
A factor to consider: it's been a long time since a Justice died in office. For decades, Justices have left the high bench by retiring, which can be timed for the end of the Term, leaving everything relatively orderly. The outgoing Justice wraps up this term, the new Justice takes office for the next Term. That's not the case here, and the situation hasn't happened very often in recent history. From what I can see, the last Justice to die in office was CJ Rehnquist, who died in 2005 -- while the Court was in recess between two Terms. Going farther back, Justice Robert Jackson died in office in 1954. He died on October 9, meaning the Term had barely begun. Then there was Justice Frank Murphy, who died in July 1949 -- again, between Terms. So a mid-Term death is an event for which there has been no precedent for something over 65 years.
A term runs from early October to late June, nine months. The Court is almost exactly halfway through that. That means a lot of cases that have been argued but not decided. Its custom in case of a replacement is to re-argue cases unless the replacement agrees to cast no vote in the case. Just handling the cases already argued is going to be a major problem. The Court's calendar schedules arguments relatively early in a Term, leaving the Court time to decide them late in the Term. There have already been 26 argument days (and four more scheduled for this month), with 14 left for the rest of the Term. In terms of arguments, the Court is 2/3 to 3/4 through its task. In terms of rulings, the decisions so far rendered have been the "slam dunks," which the Court likes to get out of the way early. Of those 18 rulings, six were per curium (essentially consensus, not signed by any judge) and another five were unanimous. In short, the Court's calendar this Term will likely be in chaos for some time.
How long would such a recess appointment endure? The Framers seem to have regarded "recess" with an eye to the gap between two Congresses, not with an eye to shorter breaks, and the clause says that the recess "Commissions which shall expire at the End of their next Session." If a shorter recess qualifies for appointments, and the courts say it does, does the "end of their [the Senate's] next session" relate to the next time they take a recess, or to the end of this Senate late this year, or to the end of the next Senate, 2+ years from now? Hard to say, given how the courts have played around with the language (the clause says it allows appointments for "Vacancies that may happen during the Recess of the Senate," but the courts have said that covers vacancies that happened while the Senate was in session and remain open when it recesses).
Some further issues, and ones that might make a recess appointment unattractive:
1. Congress may be in a recess too brief to activate the appointments clause. In NRLB v. Canning, the Supreme Court faced that issue, and stated "We therefore conclude, in light of historical practice, that a recess of more than 3 days but less than 10 days is presumptively too short to fall within the Clause." If my counting is correct, this is a 9 or 10 day recess (Feb. 12-22) and thus on the borderline.
2. Congress may have a way around. The same case noted that "the 2-year life of each elected Congress typically consists of two formal 1-year sessions.... The Senate or the House of Representatives announces an inter-session recess by approving a resolution stating that it will "adjourn sine die," i.e., without specifying a date to return (in which case Congress will reconvene when the next formal session is scheduled to begin)." Note "typically." NLRB also noted that "The Constitution thus gives the Senate wide latitude to determine whether and when to have a session, as well as how to conduct the session. This suggests that the Senate's determination about what constitutes a session should merit great respect." Congress might thus be able to declare the first session at an end, begin a second session, declare that at an end, and begin a third session. The recess appointment (and any others made to date) would terminate at the end of the second session.