Students at the mock trial Thursday reenacting the case of Tinker v. Des Moines Independent Community School District in the ceremonial courtroom of the U.S. Court of Appeals for the D.C. Circuit. (Michael Robinson Chavez/The Washington Post)

As she stood before local students in a federal courtroom in Washington, Mary Beth Tinker held aloft a replica of the black armband that had brought her notoriety — and students like them protections of their freedom of expression.

On Thursday, nearly 50 years after Tinker wore an armband to her Iowa school to protest the Vietnam War — and was suspended — she appeared at a mock trial reenacting her case before students from the Washington area.

In the past year, local students have walked out of class to protest election results and to draw attention to the plight of undocumented immigrants.

And their rights to those protests are bolstered by the 1969 Supreme Court decision in Tinker’s case, when a majority of justices ruled that students and teachers do not “shed their constitutional rights to freedom of speech or expression at the schoolhouse gate.”

It was interesting to see that “something that happened so long ago . . . is still so relevant today,” said Soracha McGrath, a 17-year-old senior at the School Without Walls in Foggy Bottom.

Eighth graders from G. James Gholson Middle School in Prince George’s County watch the mock trial. (Michael Robinson Chavez/The Washington Post)

In a case brought by the American Civil Liberties Union over Tinker’s suspension, the Supreme Court ruled the First Amendment applied to public schools and that school officials could not censor student speech unless it disrupted the educational process. A black armband, judges ruled, was not disruptive.

“It’s not just history. The decision in this case governs how students and school officials deal with expression in schools today,” Judge David S. Tatel of the U.S. Court of Appeals for the D.C. Circuit said Thursday.

Tatel, along with Judge Sri Srinivasan, also of the U.S. Court of Appeals for the D.C. Circuit, and Judge Ketanji Brown Jackson of the U.S. District Court for the District of Columbia, presided while experienced lawyers reenacted Tinker v. Des Moines Independent Community School District before about 200 students.

Some in the audience in the ceremonial courtroom of the appeals court were eighth-graders, the same as Tinker when at 13 she wore the armband in 1965.

“These kids need to speak up for themselves, and it is powerful when they do that,” Tinker, 65, said Thursday.

Unlike typical court proceedings, where the audience in a courtroom is hushed, students were animated, amused by some of the questions asked by the judges during oral arguments, including about how many students were punched every day in the Des Moines schools.

Tinker, a retired nurse who lives in Van Ness, arrived Thursday to court wearing a pin of the late Supreme Court Justice Thurgood Marshall, a relentless voice for minorities and civil rights in a six-decade legal career, and a red ribbon for Yoselis Region Barrios, a 16-year-old student of Capital City Charter School who was killed last month in the District.

Students didn’t take their eyes off the lawyers and judges during the arguments, listening intently to the case and how it led to their right of expression in school.

After the reenactment finished, students crowded around Tinker as she asked them what they wanted to change in the world. Tinker had described how she was raised in a family headed by her Methodist minister father and a mother who urged their children to act on their religious ideals.

Tinker “fought for something she believed in,” said Eliora Brown-Egue, a 13-year-old eighth-grader at Alice Deal Middle School in Tenleytown. “It was amazing to learn about a part of history from someone who was there.”

Before starting a career speaking to students, Tinker was a nurse at Prince George’s Hospital Center.

She decided to travel the country and talk to students about their right to express themselves, she said, because “I thought, maybe I can be an inspiration.”

When Tinker travels to speak as in Thursday’s reenactment, she tells stories of other young people who spoke up throughout history.

Telia Walton, a 17-year-old senior at the School Without Walls, said the event was “not just teaching us about the case,” it was “inspiring us.”

Tinker and the case “made us feel like we could do the same thing,” Walton said.