[Enchante]

Depends upon what statutes and/or constitutional issues they are addressing - I haven't seen the opinion yet but this quotation suggests they are relying upon an interpretation of the "equal protection clause" of the 14th Amendment (US Constitution), unless CA also has an equal protection clause that they are referring to??

"the interest in retaining the traditional and well-established definition of marriage — cannot properly be viewed as a compelling state interest for purposes of the equal protection clause, or as necessary to serve such an interest."

[lastchance]

Yes the ruling is referencing CA equal protection clause.