PARIS (AP) — France’s top court has upheld a ruling ordering a Lebanese-Canadian academic to stand trial over a deadly 1980 bombing outside a Paris synagogue.

The Court of Cassation delivered the ruling Wednesday, upholding a decision by an appeals court in January that Ottawa sociology professor Hassan Diab must face trial.

Diab, now 67, is in Canada. He has denied involvement in the October 3, 1980 bomb attack in Rue Copernic in western Paris, which killed four people and wounded 46.

Diab’s lawyer said he is considering taking the case to the European Court of Human Rights.

After decades of investigations, Canada authorized Diab's extradition to France at the end of 2014. He spent three years in pretrial detention and then returned to Canada after a lower French court ordered his release, citing lack of evidence of his involvement.