A Canadian engineer cannot sue the United States after being mistaken for a terrorist when he was changing planes in New York a year after the 2001 terrorist attacks, a federal appeals court ruled Monday.

The judges of the 2nd U.S. Circuit Court of Appeals voted 7-4 to uphold a decision by a lower court judge dismissing a lawsuit brought by Maher Arar, a Syrian-born man who was detained as he tried to switch planes in 2002.

Arar sued the U.S. government and top Justice Department officials, saying the United States purposely sent him to Syria to be tortured days after he was picked up at John F. Kennedy International Airport based on a false tip from Canada that Arar had ties to Islamic extremists. It said he was only allowed to see a lawyer once despite his repeated efforts to receive representation.

Syria has denied he was tortured. The Canadian government agreed to pay him almost $10 million after acknowledging it had passed bad information to U.S. authorities.

The appeals court said in a majority opinion that it cannot let Arar use the courts to press his claims against the U.S. government without Congress enacting legislation that spells out exactly how a case as unusual as Arar's claims can be brought and what potential remedy exists.

Otherwise, the court said, allowing the lawsuit to proceed would "offend the separation of powers and inhibit this country's foreign policy."

At stake in the lawsuit was the court's role in reviewing the practice of "extraordinary rendition" in which someone suspected of supporting terrorism is transferred to a foreign nation for imprisonment and interrogation without formal charges, trial or court approval.

The appeals court said it was hesitant to create "a new damages remedy that Congress has not seen fit to authorize."

It added: "Even the probing of these matters entails the risk that other countries will become less willing to cooperate with the United States in sharing intelligence resources to counter terrorism."

The Center for Constitutional Rights, which represented the Ottawa resident, said its lawyers had not seen the ruling and could not immediately comment.

The appeals court ruling came almost a year after the full 2nd Circuit heard nearly three hours of arguments in front of several hundred spectators in the building's largest courtroom.

A three-judge appeals panel earlier last year upheld a Brooklyn judge's finding in 2006 that the government did not violate the Torture Victim Protection Act. The law allows U.S. courts to assess damages against perpetrators of human rights abuses committed abroad.