A top attorney for opponents of California's same-sex marriage ban on Sunday denied that the ruling this past week overturning that ban constitutes judicial activism, saying the judge in the case was merely applying the Constitution to end discrimination.
Former Solicitor General Theodore Olson predicted the Supreme Court would agree.
"It is not judicial activism. It is judicial responsibility in its classic sense," Olson told "Fox News Sunday."
U.S. District Judge Vaughn Walker, one of three openly gay federal judges in the country, ruled Wednesday that California's Proposition 8 was unconstitutional. The case goes next to federal appeals court and many, including Olson, expect it will ultimately end up before the Supreme Court.
But even though critics argue Walker wrongly invalidated the decision of 7 million California voters, Olson denied the suggestion that the judge in the case looked beyond the law in reaching his conclusion.
"It's not judicial activism when judges do what the Constitution requires them to do and they follow the precedent of previous decisions of the Supreme Court," he said. "This is what judges are expected to do."
The case could have wide-reaching ramifications for other state laws restricting same-sex marriages. Thirty states have constitutional bans on same-sex marriage similar to California's and while the 9th Circuit Court decision, wherever it falls, would not have to be taken as binding precedent in other circuits, it could influence similar challenges elsewhere.
The ruling in the appeals court would also impact the nine Western states that fall under its jurisdiction -- eight of which have constitutional bans on same-sex marriage. And a Supreme Court ruling, should it reach that point, would have national reach.
Jordan Lorence, senior counsel with the Alliance Defense Fund defending the ban, told FoxNews.com earlier in the week that Walker's decision was a "contradiction" of the Constitution. He expressed confidence that those fighting to uphold the ban will ultimately prevail, calling Walker's interpretation "clearly wrong."
But Olson, a prominent conservative lawyer, cited the equal protections afforded under the 14th amendment and applauded Walker's ruling.
"We're not talking about a new right here," he said. "Most people use the term judicial activism to explain decisions that they don't like."
Olson said his side was not taking "anything for granted," but suggested the Supreme Court would hand his team a victory in the end.
"California has no rational basis for continuing this discrimination. When that gets to the Supreme Court, I think that will be persuasive to all of the justices on the Supreme Court," he said.
Olson served as the U.S. solicitor general under the George W. Bush administration. He is arguing the Proposition 8 case with David Boies -- both lawyers represented Bush in the court battle against former Vice President Al Gore during the disputed 2000 presidential election.