Jan. 9 (UPI) — A man convicted of encouraging Muslims to fight overseas after the Sept. 11, 2001, terrorist attacks engaged in lawful free speech, a federal appellate court ruled Friday.

The 4th U.S. Circuit Court of Appeals’ three-judge panel in Virginia vacated Ali al-Timimi’s convictions after ruling he engaged in constitutionally protected free speech and did not violate any laws.

“The First Amendment does not permit the government to imprison a person for speech unless that speech falls within a narrow and well-defined category of unprotected expressions — such as incitement of imminent lawless action or speech that intentionally solicits or facilitates a specific crime,” Circuit Judge James Wynn said in the unanimous ruling.

“Ali al-Timimi was convicted based entirely on words he spoke in the immediate aftermath of the Sept. 11, 2001, attacks — words that were inflammatory, disturbing and deeply offensive, but that urged no concrete criminal plan and did not provide operational assistance for the commission of any particular offense,” Wynn wrote.

Al-Timimi was an “Islamic lecturer” in northern Virginia and has been serving a sentence of 15 years to life after being convicted of treason following the Sept. 11, 2001, terrorist attacks on the World Trade Center, the Pentagon and hijacking United Airlines Flight 93, which crashed in a Pennsylvania field, killing all 40 on board.

He was charged and convicted after holding secret meetings with others in Washington, D.C., suburbs during which he encouraged others to join an Islamist group that is a designated foreign terrorist organization, according to Politico.

“Plenty of speech encouraging criminal activity is protected under the First Amendment,” Wynn said.

“The First Amendment’s protection does not depend on the popularity or palatability of the message conveyed,” he added. “On the contrary, it is most vital when speech offends, disturbs, or challenges prevailing sensibilities.”

Also ruling on the case were Circuit Judges Stephanie Thacker and Pamela Harris. Former President Barack Obama appointed Wynn, Thacker and Harris to the federal appellate court.

A federal jury in Alexandria, Va., in 2005 convicted al-Timimi on 10 criminal charges that included aiding and abetting in violation of the Neutrality Act, soliciting treason and firearms violations.

He encouraged others to travel to Pakistan and be trained by the Islamist group Lashkar-e-Taiba to fight against U.S. troops in Afghanistan, prosecutors argued.

Al-Timimi’s case was part of a larger prosecution of what federal prosecutors called the “Virginia Jihad Network” and involved many other defendants who were convicted on similar charges and sentenced to prison.

Rays of light burst off a building at 1 Liberty Plaza to silhouette two firefighters surveying Ground Zero at dawn on September 15, 2001. Photo by Chris Corder/UPI | License Photo