Liberals rejoiced in his decisions barring the execution of minors, recognizing a constitutional right to same-sex marriage, defending free speech and protecting legal abortions.
Conservatives revered iconic decisions like Citizens United (protecting the rights of corporate speech) and Gonzales v. Carhart (upholding a federal law that criminalizes partial-birth abortions).
Kennedy's jurisprudence reflected a unique mix of libertarian and natural-rights elements. To him, the Constitution may not have been the "living" document embraced by his liberal colleagues, but it evolved in its application to new forms of expression and association.
That evolution often meant discarding prior doctrines and the time-honored judicial norm of stare decisis --- the notion that courts should "stand by things decided." Absent significant changes in the underlying law or conditions, courts avoid overturning precedent in the interests of institutional consistency and integrity.
Kennedy's cases should rest comfortably within that cocoon of tradition. Indeed, at one time, Kennedy insisted that "the whole object of the judiciary is to ensure stability, continuity, and so we pride ourselves on the fact that there is little change."
But contained in his long tenure, and in many of his most historic cases, is an occasional disdain for precedent; his most important rulings were built on the ashes of prior decisions. In Lawrence v. Texas, for example, Kennedy tossed out the nearly two-decade-old ruling in Bowers v. Hardwick, citing changes in legal and social views.
"Bowers was not correct when it was decided, and it is not correct today," he wrote. "It ought not to remain binding precedent." In June, he advanced his attack on stare decisis even further, authoring a 5-to-4 decision that cavalierly dispensed with a major 1992 tax precedent. Then he signed onto a majority opinion overturning an important 1977 case about union dues. Kennedy began his career standing by things decided but ended it creating new doctrines.
Unwittingly, Kennedy may have crafted the perfect weapon for activist judges. His historic rulings may stand the test of time. But if any of his major opinions are voided by future courts, the weapon may not bear the fingerprints of his more conservative replacement but rather, in a strange way, his own.
In the recent South Dakota v. Wayfair decision, Kennedy wrote for a 5-to-4 majority that states may tax online purchases. The court's previous standard, from Quill Corp. v. North Dakota in 1992, allowed state taxation only where a business has a physical presence --- a paradigm that guided states and Congress for 16 years, until Wayfair.
Kennedy dismissed the notion that he should follow the earlier doctrine in the interest of institutional consistency, quoting a 2009 opinion that "stare decisis is not an inexorable command." Given the court's shifting interpretation of the Constitution's commerce clause, he said, "the Court should be vigilant in correcting the error."
On Wednesday, Kennedy signed on to yet another opinion driving a stake into the heart of stare decisis. In Janus v. AFSCME Council 31, the majority set aside a precedent established in 1977 in Abood v. Detroit Board of Education. In that case, the court upheld the constitutionality of requiring nonunion workers to pay dues to unions that negotiate on behalf of all workers.
Justice Samuel Alito's majority opinion in Janus declared Abood "poorly reasoned" and said the doctrine of stare decisis is "weakest" when deciding matters of constitutional law (as opposed to statutory interpretations). By joining the majority, Kennedy endorsed the view that a past case, such as Abood, can be set aside based on the "quality" of its "reasoning."
The problem for Kennedy: That "weakest" application of stare decisis could be applied to many of his most important decisions, which turn on his view of inherent rights contained, but not always enumerated, in the Constitution.
Rejecting the notion that stare decisis is an "inexorable command" and downgrading it to a pliable consideration will allow reversals of his opinions. Just as the court could set aside the 1992 decision in Quill Corp., a more conservative successor could find that equally corrective measures are needed for Kennedy's opinion (with Sandra Day O'Connor and David Souter) in Planned Parenthood v. Casey, the 1992 case preserving the right to abortions.
The uncomfortable fact is that Kennedy's legacy is as fragile as it is immense. Many of his rulings were decided by a one-justice margin: He supplied the critical fifth vote upholding the right to burn the American flag in Texas v. Johnson in 1989, declaring, "It is poignant but fundamental that the flag protects those who hold it in contempt." He was with the 5-to-4 majority in Kennedy v. Louisiana (2008), which said convicts could not be put to death for child rape. In the 5-to-4 Boumediene v. Bush ruling (2008), he afforded Guantanamo detainees basic due process protections. Only five justices voted to decriminalize gay sex in Lawrence v. Texas (2003). The same number found a right to same-sex marriage in Obergefell v. Hodges (2015).
With his legacy dangling by a single vote - his own - Kennedy advanced views that were not necessarily shared even by some of the justices who joined his opinions. He fought for decades to create a controversial constitutional "right to dignity," for instance.
The right to choose abortion, he wrote in Casey, is based on "personal dignity and autonomy," which "are central to the liberty protected by the Fourteenth Amendment." He elaborated on this concept in a variety of later cases involving issues from gay rights to prisoner rights. In declaring a constitutional protection for same-sex marriage, Kennedy did not emphasize equal protection but rather esteem: "They ask for equal dignity in the eyes of the law. The Constitution grants them that right."
The idea of a constitutionally protected right to dignity infuriates many constitutional textualists on the right. For them, this is a creature of Kennedy's imagination, not the Constitution. If Trump's next court nominee doesn't share Kennedy's view (which he or she is unlikely to do), his replacement might wind up citing Kennedy's own words in Wayfair to scrap "equal dignity" as any kind of legal standard.
The risk of something like that is even greater after Kennedy and his colleagues effectively punted, in their June decision in Masterpiece Cakeshop v. Colorado Rights Commission, a case in which a same-sex couple was denied a wedding cake by an observant Christian baker. Rather than resolve the conflict between free speech and anti-discrimination laws, the court sent the case back to a lower court with an ambiguous demand for reconsideration. If a future court decides to hear Cakeshop, the justices would have a ready-made opportunity to dispense with the dignity rights of LGBT consumers.
In fairness to Kennedy, there are strong arguments against stare decisis, which seems more often honored on the court in the breach. Dissenting justices on the wrong side of a 5-to-4 split often lament that precedents should be respected. (In Janus, Justice Elena Kagan called Kennedy and his colleagues "black-robed rulers" who "subvert[ed] all known principles of stare decisis.") Kennedy's opinions reflected changes not just on the court but in society at large, and his rulings were hardly the only ones to do this.
Of course, Kennedy doesn't just have a couple of cases at stake. Much of his legacy is in the balance, and in his final week he offered his strongest support for the rationale that could undo it. At 81, he not only provided President Donald Trump with ample time to secure a more conservative nominee but provided that nominee with ample means to discard his most signature rulings.
Kennedy once said, "Sometimes you don't know if you're Caesar about to cross the Rubicon or Captain Queeg cutting your own tow line." This is certainly one of those moments.
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