Attorney David Boies on Sunday asserted that the Supreme Court last week declared all gay marriage bans unconstitutional.

Boies co-argued the case against California's Proposition 8.

Opponents of gay nuptials have said that they found solace in the fact that the court narrowly decided the Proposition 8 case.

“The court … did not create a right out of thin air to redefine marriage throughout this country. What it did do is rob the proponents of Proposition 8 after they had seen utter lawlessness with Governor Brown and the attorney general refusing to defend the law,” Brian Brown, president of the National Organization for Marriage (NOM), a proponent of Proposition 8, said Sunday on This Week.

(Related: NOM's Brian Brown vows to “roll back gay marriage” wherever it exists.)

But in a separate appearance on CNN's State of the Union, Boies took even that sliver of hope away from opponents.

“First, remember that the United States Supreme Court found that the plaintiffs in this particular case had standing to attack Proposition 8, but the people who were supporting Proposition 8 did not have standing to appeal our victory in the trial court,” Boies told host Candy Crowley. “So that reinstates the trial court decision that says that all bans on gay and lesbian marriage violate the equal protection and due process clauses of the 14th Amendment.”

“Not just in California. That is a ruling that says under the constitution, not just in California, but under the constitution, which of course is a national constitution, the 14th Amendment applies to all 50 states ...”

“But you know, David, a lot of people thought that this was more about states' rights, allowing the states to decide for themselves,” Crowley interrupted.

“If they were allowing the states to decide for themselves, they would have allowed California to decide for itself. California passed Proposition 8. So, what the court was doing was invalidating California's choice, and that's exactly what the courts are supposed to do under the 14th Amendment,” Boies responded.

(Watch the entire segment at CNN.)

In recent days, some supporters, Boies among them, have said that marriage equality will blanket the nation in 5 years.