Gay former congressman Barney Frank took a pot shot at the late Supreme Court Justice Antonin Scalia this week during an MSNBC panel on President-elect Donald Trump’s Twitter activity.

Frank was discussing Trump’s tweet Monday about those who burn the American flag.

“Nobody should be allowed to burn the American flag – if they do, there must be consequences – perhaps loss of citizenship or year in jail!” Trump tweeted.

Frank told MSNBC’s Chris Matthews not to underestimate Trump’s “shrewd tactical sense.”

“(Trump) has a great ability to find out what might really anger people, and he’s clearly got problems,” Frank said, citing Trump’s claim that millions of people voted illegally in the 2016 election.

Frank contends Trump’s Twitter comments are a “calculated strategy” to undermine the mainstream media, then zinged Scalia, whom Trump and other conservatives have praised since he died in February.

“Scalia wrote the opinion, he was very strongly on the other side of (flag burning), and he cited Scalia as his favorite justice,” Frank told Matthews. “I think there was a pronunciation problem there. You know, Scalia was actually the leading advocate for fag burning, not flag burning.”

Matthews laughed along with Frank at the comment before coming to his senses.

“That’s not funny,” Matthews said, still laughing.

Scalia spoke about flag burning and the Constitution in a 2012 interview with CNN that made it clear that while he’s not a fan of torching Old Glory, it’s considered protected free speech.

“If I were kind, I would not allow people to go around burning the American flag,” Scalia said. “However, we have a First Amendment, which says that the right of free speech shall not be abridged – and it is addressed in particular to speech critical of the government.”

“That’s the main kind of speech that tyrants would seek to suppress,” he said.

CNN reports:

The issue has been twice decided by the Supreme Court, which as the nation’s highest court has final say on whether laws are unconstitutional. Only an amendment to the Constitution itself, or a subsequent decision by the Supreme Court, would overrule the court’s decision.

The cases were Texas v. Johnson in 1989, and US v. Eichman in 1990. The former case stemmed from a flag burning protest at the 1984 Republican National Convention and a Texas law banning desecration of a venerated object, and the latter responded to a bill from Congress that made harming the flag illegal.

In both cases, the Supreme Court ruled that burning a flag is an act of expression and “symbolic speech,” and exactly they type of action that the First Amendment was designed to protect.

While politicians have continued to introduce bills and proposed constitutional amendments to ban flag burning, they have failed to advance, in large part because of the First Amendment issue.

Ironically, one of the attempts to criminalize flag burning, the Flag Protection Act of 2005, was co-sponsored by Sen. Hillary Clinton, according to the news site.

The flag burning issue has become increasingly contentious in the weeks following the 2016 election, as college students and social justice warriors across the country have set the American flag ablaze in protest of Trump’s historic victory.