Final answer:
The recognition by California of a marriage performed in New York State reflects the principle of the full faith and credit clause, which pertains to state-to-state relations and was central to the recognition of same-sex marriages.
Step-by-step explanation:
When California recognizes the marriage of a couple married in New York State, it is referring to the full faith and credit clause. This clause, found in Article IV of the U.S. Constitution, requires each state to recognize the public acts, records, and judicial proceedings of every other state. The relevance of the full faith and credit clause rose significantly following debates over the recognition of same-sex marriages, which culminated in the landmark Supreme Court decision in Obergefell v. Hodges in 2015. This decision mandated that same-sex marriage is a fundamental right protected by the Due Process Clause and the Equal Protection Clause of the Fourteenth Amendment.