Last year, the Iowa Supreme Court struck down a gay-marriage ban on the grounds that it violated the due process and equal protection clauses of the state constitution. The unanimous decision was written by Justice Mark Cady, a conservative placed on the court by the former Republican governor Terry Branstad. In 2008, the Connecticut Supreme Court struck down a comparable prohibition in an opinion written by Justice Richard Palmer, an appointee of Governor Lowell Weicker, a three-term Republican senator who became an independent. The Massachusetts Supreme Court ruling was written by Chief Justice Margaret Marshall, named to the court by one Republican governor (William Weld) and elevated to chief justice by another (Paul Cellucci).
This summer's other major ruling on gay marriage, along with Tauro's, will come from the federal district court in California, where Chief Judge Vaughn Walker will decide whether to overturn the state's Proposition 8, which bans gay marriage. The betting is that he will, which would be notable not only because of his political lineage but because Walker's nomination by Ronald Reagan was thwarted by Democrats -- led by the current House Speaker, Nancy Pelosi -- who believed he was prejudiced against homosexuals. They were mistaken. Reappointed by George H.W. Bush and this time confirmed, Walker demonstrated no prejudice.
The Tauro and Walker rulings are federal decisions, and particularly salient as such. For years, federal courts were considered hostile territory for gay rights advocates, ever since Bowers v. Hardwick, the first of three Supreme Court decisions affecting prospects for gay marriage. The Bowers decision of 1986 upheld states' right to criminalize same-sex intimacy, and did so in a sneering majority opinion -- written by Byron White, a Democratic appointee -- that suggested a distinct contempt for any claims to gay rights.
Two subsequent decisions hinted at a thaw. In 1996, Romer v. Evans derailed an attempt to overturn state and municipal anti-discrimination laws, on which activists had focused after Bowers. In contrast to that decision, the majority opinion in Romer was strikingly respectful; it, too, quoted Harlan's dissent in Plessy v. Ferguson. In 2003, Lawrence v. Texas invalidated state sodomy laws, explicitly overruling Bowers in the process. The Court further held that ''the intimate, adult consensual conduct at issue'' was protected under the Fourteenth Amendment.
Both decisions were written by Justice Anthony Kennedy, another Reagan appointee. If either of this summer's federal decisions get to the Supreme Court, Kennedy will likely cast the deciding vote -- which would, in the end, be most fitting.
What all these judges share is their distinctiveness from Republican appointments over the last two decades, who tend to be activists affiliated with conservative outfits like the Federalist Society -- think John Roberts and Samuel Alito. This makes the Republican pedigrees of the judges moving gay marriage toward legality all the more striking, particularly in how it contrasts with conservative outcries about judicial activism. But more than that, it's a gauge of how far from the mainstream modern conservative jurists have drifted.
Joshua Green writes a weekly column for the Boston Globe.