Ruth Bader Ginsburg makes her Washington National Opera debut with a role mirroring her real life

Tenor Lawrence Brownlee escorts Justice Ruth Bader Ginsburg at the curtain call of “The Daughter of the Regiment.” (Scott Suchman for the Washington National Opera)

A standing ovation for merely appearing on stage? Just another Saturday night for Ruth Bader Ginsburg.

The Supreme Court justice and known lover of the arts had a one-night only performance at the opening of Washington National Opera’s “The Daughter of the Regiment.” The show, which is a little more Disney than diva, is about a young French woman who grows up on the battlefield, but is whisked away from her true love once she reaches marrying age so that she can join high society and find a suitable match.

By intermission, Ginsburg still hadn’t made her appearance on stage, but Newt and Callista Gingrich (they have season tickets to opening performances) and former CIA head Michael Hayden were spotted in the crowd.

But the audience didn’t have to wait too long for Ginsburg’s Duchess of Krakenthorp to make her debut in Act II.

“I did this for the first time; I had a speaking part. I never have a singing part because I’m a monotone,” Ginsburg said later in the evening at the cast party.

In an instance of art imitating life, the duchess gives the young woman rules for holding a position of rank. “Applicants seeking a station so exalted must possess adequate financial resources. They must have the fortitude to undergo strict scrutiny. Their character must be beyond reproach.” (Sound familiar?)

Later, the Duchess of Krakenthorp asks to see a birth certificate. (Okay, is Notorious R.B.G. trolling us?)

The duchess finishes with this bit of advice: “Dropping traditions that have worked and are continuing to work is like throwing away your umbrella in a rainstorm because you are not getting wet.”

By this point, many in the audience were on their feet again (the Gingriches stayed in their seats), and some were whispering to their seatmates about whether this was the original script.

After the performance, the cast members and VIP guests — including former senator Elizabeth Dole, Ambassador of Switzerland Martín Dahinden and his wife Anita Dahinden — moved upstairs to the Kennedy Center’s East Terrace for a buffet, open bar and chance to mingle with the 83-year-old justice. Seeing as this was more of a bow tie and shawl crowd, Ginsburg received more requests to autograph programs than to take selfies.

So what about that telling dialogue? “They gave me the script, and I rewrote it with lines that fit me,” Ginsburg said. (According to The Post’s classical music critic Anne Midgette, that is common for the duchess role.)

But when asked to share her thoughts on the political events of the week, the justice had no comment. The art will have to speak for itself.