Lyle Denniston writes at SCOTUSblog:
The brief was limited to defending same-sex marriage under an “equal protection” standard, leaving unmentioned the other constitutional argument that some challengers to state bans have made: that marriage is a fundamental right that cannot be closed to such couples, a “due process” argument.
The government’s new filing, signed by U.S. Solicitor General Donald B. Verrilli, Jr., and other Justice Department officials and staff lawyers, sought to persuade the Court to embrace a constitutional test that this administration has been pressing for some time in gay rights cases.
It called for what is known as “heightened scrutiny” — the middle level of three ascending tests for judging claims that laws discriminate on the basis of a forbidden personal trait. The easiest standard to meet is “rational basis,” and the toughest is “strict scrutiny.”
Under the middle level, a law that is challenged as discriminatory can be upheld only if it serves an “important government objective” and its terms are “substantially related” to such a policy goal.
In a series of decisions in recent years that have added to gay rights, the Supreme Court has never specified an explicit standard for use in the field of sexual orientation. At times, it has seemed to adopt something like “rational basis-plus,” but it has never given a specific definition of the test or tests it has used.
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