This is where they artificially construct "classes" in order to abuse the concept of Equal Protection.
Marriage is by definition a legal union between a man and a woman. Nothing else. Sexual preference is none of the states business nor is it part of the state's contract. Regardless of their "sexual preference" two people of the opposite sex may not marry each other. And regardless of their sexual preference, those same people are legally entitled to marry someone of the opposite sex.
It is perfectly equal unless you accept the bizarre notion that the state can define new classes of citizens based upon something as personal and legally unprovable as sexual preference.
But per So Cal Rocket's synopsis, the judge starts out using a rational basis test, suggesting that the law does not have a rational relationship to a legitimate state purpose. Then he jumps to a denial of equal protection, which would call for strict scrutiny.
Since when is being a homosexual a suspect category?
One more time J. Kramer: you guys in the gowns interpret the laws, while the guys/gals in suits make them.
(Let's hoist them, whaddya say? "We are a notion of laws, not men." US v. Nixon, 1974)