"...and by and with the Advice and Consent of the Senate, [The President] shall appoint Ambassadors, other public Ministers and Consuls, Judges of the supreme Court, and all other Officers of the United States..." - Article II, Section 2, Clause 2, U.S. Constitution
This week out on the campaign trail, Hillary Clinton (D) told supporters that she thought that President Obama on the High Court would be a 'great idea.'
In today's political climate, this kind of campaign statement is almost certainly going to further polarize the party faithful -- but then again, Hillary might have a good (and historically useful) strategy to employ.
To date, William Howard Taft has been the only president to later become a justice on the Supreme Court.
Taft's overall impact on the high court had been overwhelming during his presidency. As a presidency that was largely seen as a failure, he shaped the Supreme Court with six new nominations, equaling Washington, Lincoln, and FDR for the most approved nominations to the high court.
President Harding nominated Taft to be the chief justice, quickly accepted by Taft and overwhelmingly approved by the Senate (60-4).
Taft had a lot of legal experience prior to being president, serving as a judge in the federal courts, but his influence as chief justice dominated American politics for almost a decade after leaving his lackluster presidency behind.
Obama as a SCOTUS Justice?
It's unlikely that President Obama could ever reach Senate cloture to be approved as a justice, but it would definitely make for interesting party-line politics.
While holding a law degree, he does not have much experience in the federal court system, something that could definitely be a drawback. But where he would flourish is the fact that within the Democratic Party he is still popular, and his policies are still valued.
The real point in all of this is that presidential term limits often 'kill' the ability of a party's darling to keep pressure on the national agenda -- and often the party has to formulate new platforms (even though satisfied with the old ones) to keep from looking old and stale in general elections.
From Hillary's perspective, this type of statement is unlikely to politically backfire. Her opponents already bombard her with accusations of what types of "liberal judicial activists" she will appoint, but her giving an inkling to the base as to the types she would nominate might help her case.
From a vetting perspective, the last 8 years have brought out all of Obama's flaws and faults -- whether real, made-up, or just perceived. This would be an incredible bonus: having a potential nominee in hand that has an iron-clad vetting.
Instead of the senatorial side-show being about gotcha-politics on every stupid thing the nominee has done since they were an adult, it would be completely on partisan issues of his own presidency. If anything, issues might be discussed.
Who 'Are' These Politicians Who Survive the Vetting Process?
A person who hasn't made any dumb mistakes, regrettable actions, or foolish young-adult pranks is a freak of nature--and yet we actively hunt for this natural anomaly as desirable for the role of politician.
Gotcha-politics makes for interesting television watching, but it seldom inspires or brings out the best people to be candidate.
Politics has become almost as bad as reality television, with opposing teams willing to engage in an all-star 'Politician Death-Match."
Therein is the novelty of Justice Obama -- he's taken his licks in the court of public opinion and really doesn't have (or at least shouldn't have) much more baggage to offer.
Great for the nomination process; very bad for entertainment value.