In overwhelming numbers, the U.S. Congress voted on Wednesday to override President Barack Obama’s veto of the Justice Against Sponsors of Terrorism Act. The bill marks the first time one of Obama’s 12 vetoes has been overridden.

JASTA allows survivors and victims’ families of the 9/11 terrorist attacks to sue the government of Saudi Arabia, which has long been suspected to have played a role in supporting the numerous Saudi Arabian men responsible for 
the attacks.

Opponents argue that, because JASTA allows for lawsuits to be brought against another country, the bill breaks international law’s principle of sovereign immunity, which states that another country cannot be brought to the courts 
of another country.

Proponents of the bill, an almost unanimous coalition of Republicans and Democrats, argue that there are already exceptions to the principle of sovereign immunity on the books.

“The issue is fundamentally about whether someone would have the opportunity to raise their concerns in the judicial system,” said Sen. Ron Wyden. “It seems to me that it is appropriate — particularly in light of the families — that they should have a chance to raise their concerns 
in court.”