The Supreme Court appeared divided Tuesday in a cross-border shooting case that has the potential to further strain the relationship between the United States and Mexico.

The case, Hernández v. Mesa, centers on the parents of a 15-year-old Mexican teen, who are appealing to the Supreme Court for the right to sue the U.S. border patrol agent who shot and killed their son, Sergio Hernández, in 2010.

The shooting happened while Hernández was playing a game with his friends in which they dared each other to run up and touch an 18-foot fence along the U.S. border.

ADVERTISEMENT

Hernández's parents claim the agent, Jesus Mesa, violated the Fourth Amendment when he used deadly force against their son, who was unarmed and on the Mexican side when he was shot in the head.

The case comes amid President Trump’s push to build a wall along the southern border, the lynchpin promise of his presidential campaign.

Justice Anthony Kennedy on Tuesday suggested the issue in the case is a critical area of foreign relations, and questioned why the court was involved.

“You've indicated that there's a problem all along the border,” Kennedy told Robert Hilliard, the attorney representing Henandez’s parents.

“Why doesn't that counsel us that this is one of the most sensitive areas of foreign affairs where the political branches should discuss with Mexico what the solution ought to be?”

Hilliard argued that there is no alternative remedy for the family if the court refuses to allow his clients to sue Mesa.

Mesa and the federal government claim Fourth Amendment protections do not extend outside the U.S.

Since U.S. law governs U.S. border patrol agents, though, Justice Ruth Bader Ginsburg asked why the officer should not be held accountable.

“And the instruction from the United States is very clear: Do not shoot to kill an unarmed, non-dangerous person who is no threat to your safety. Do not shoot to kill. That's U.S. law,” she said.

Mesa’s attorney Randolph Ortega said the U.S. could have chosen to criminally prosecute his client.

It chose not to, claiming in court documents that it lacked jurisdiction since Hernández was killed in Mexico. Though Mexican officials charged Mesa, the U.S. refused to extradite him.

Even if Mesa had been prosecuted in the U.S., Justice Sonia Sotomayor said the Hernández family still wouldn’t have gotten any civil compensation for their pain and suffering.

“And, yes, there's a criminal remedy for the government to vindicate its position, but why should there be not be a civil remedy to ensure that border police are complying with the Constitution?” she asked.

Hernández's parents argue they have a valid right to sue Mesa, given the court’s 1972 decision in Bivens v. Six Unknown Named Agents. In that case, the court held that a violation of one’s Fourth Amendment rights by federal officers can give rise, in certain situations, to a right to sue for damages.

Justice Elena Kagan seemed to agree. She said to use deadly force in violation of the Fourth Amendment is at the "heartland" of the Bivens precedent.

“We don't have to make up anything new. We don't have to extend it. We don't have to create anything,” she said. “That's just Bivens.”

But Justice Stephen Breyer asked Hilliard, how the court would write a ruling in their favor without opening the door for someone hurt in a drone strike to bring a case against a member of the military.

“So what are the words that we write that enable you to win, which is what you want, and that avoid confusion, uncertainty, or decide these other cases the proper way?” he asked.

A ruling in favor of Mesa, however, has the potential to further damage the United States's relationship with Mexico at a time of high tensions over Trump's immigration policies.

Deputy Solicitor General Edwin Kneedler cited those tensions to argue on behalf of the federal government that Congress should be left to decide a remedy for the Hernández family.

“Any time the officers of one country injure someone in another country, that creates the potential for a foreign relations incident and it's illustrated here by a number of factors,” he said.

If the high court splits 4-4, the decision of the Fifth Circuit Court of Appeals in favor of Mesa stands.

A decision is likely to come before June.

This story was updated at 2:54 p.m.