When a Border Patrol agent standing in Nogales shot and killed a teen in Mexico in 2012, federal courts said the family of the boy could sue the officer for violating their son’s constitutional rights.

But when a Border Patrol agent in El Paso, Texas, shot and killed a Mexican teen in Ciudad Juarez in 2010, federal courts rejected the family’s lawsuit against the officer.

The Supreme Court is now stepping in to decide who’s right.

The high court said last week that it will consider the Texas case, and the ruling in that case is all but certain to determine the outcome of the Nogales case.

“So the question that the Supreme Court is looking at is, ‘Can these foreign nationals sue U.S. federal agents when the incident has occurred sort of transnationally, across a border?’” said Cori Alonso-Yoder, practitioner-in-residence at American University’s Washington College of Law.

Attorneys for the officers say no. Calls to attorneys in both cases were not returned. But in their filing to the Supreme Court, lawyers for the officer in the Texas case argued that letting suits proceed against agents would “undermine the Border Patrol’s ability to perform duties essential to national security.”

“Implying a private right of action for damages in this transnational context increases the likelihood that Border Patrol agents will ‘hesitate in making split-second decisions,’” argued attorneys for Border Patrol Agent Jesus Mesa, who was sued by the family of teen Sergio Adrian Hernandez Guereca.

“Because Hernandez was a Mexican citizen with no ties to this country, and his death occurred on Mexican soil, the very existence of any ‘constitutional’ right benefitting him raises novel and disputed issues,” the filing said, quoting earlier court decisions.

But advocates say there is nothing novel and disputed about an “ultimate abuse of authority – a shooting that left a boy killed.”

“The question is, can you go to court when a federal officer guns you down?” asked David Gans, civil rights director for the Constitutional Accountability Center. “This will control all other sorts of border shooting cases.”

Mesa was on bicycle patrol in El Paso on June 7, 2010, when he came across Sergio Hernandez, 15, and some friends playing a game in which they ran across a culvert that carried the Rio Grande, touched the fence on the U.S. side and then ran back to Mexico. Mesa grabbed one of the youths, but the others ran back toward Mexico.

At that point, Mesa fired at least two shots, one of which struck Sergio in the face, killing him. The Hernandez family said the agent “essentially committed a cold-blooded murder” by shooting Sergio, who was unarmed and hiding behind a bridge pillar when he was shot.

But Mesa claimed he only opened fire after the youths started throwing rocks at him and refused his orders to stop.

The FBI confirmed that report and the Justice Department, according to court documents, declined to charge Mesa after a “comprehensive” review of the case. Instead, it released a statement expressing sorrow at Sergio’s death and vowing to work with Mexico “to prevent future incidents.”

The Nogales case began on Oct. 10, 2012, when Jose Antonio Elena Rodriguez, 16, was walking toward Calle Internacional in Nogales shortly before midnight. Border Patrol Agent Lonnie Swartz was standing on the U.S. side of the border when he shot repeatedly through the border fence, hitting Jose 10 times, mostly in the back, according to court records. Jose collapsed and died on the spot, four blocks from his home.

Swartz was charged with murder but acquitted. At that point, Jose’s mother, Araceli Rodriguez, sued over her son’s death.

Both families filed Fourth and Fifth Amendment claims for excessive force and due process violations. And both claimed the agents, who might otherwise be protected from being sued, could be sued under an earlier Supreme Court case known as Bivens.

“The idea in Bivens was that even if Congress hasn’t created a statute that you could sue under, you could sue directly under the Constitution if a federal officer violated your constitutional right,” said Paul Schiff Berman, a George Washington University law professor.

Lower courts split on the lawsuits, and the Hernandez case has already been to the Supreme Court once, in 2017, when the justices sent the case back to the 5th U.S. Circuit Court of Appeals and ordered it to reconsider its rejection of the family’s lawsuit. The circuit court did, and it came to the same conclusion, saying the Hernandezes could not sue.

But the 9th Circuit came to the opposite conclusion, saying the Rodriguez family could pursue its suit against the officer.

The government argued that the 9th Circuit made the wrong decision. But the Solicitor General urged the Supreme Court to take the Texas case and put the Nogales case on hold while the court determines whether Bivens can extend to “an injury inflicted on a foreign citizen in another country’s sovereign territory.”

The government in both cases says it shouldn’t. Not only has the court been reluctant in recent years to extend Bivens, but doing so would intrude on Congress and muddy the government’s ability to conduct diplomacy, lawyers argue.

Swartz’s attorneys argued that letting the lawsuits proceed would be “an extraordinary usurpation of the role of Congress, which is far better situated to evaluate and weigh the impact” of allowing such cross-border lawsuits. That Congress has not created such a law is no accident, they say.

But Rodriguez’s attorneys argue that diplomacy would not be affected, since this is a case of “a single agent who personally and directly violated federal policy in using unjustified deadly force.” Deferring to congressional inaction would leave the family with no alternative remedy, they say. There would be no question Swartz could be sued if Sergio was a U.S. citizen, the family’s attorneys argued.

“The court of appeals rightly rejected the argument that a reasonable officer might believe it was constitutionally permissible to stand at the border fence and, without justification, fatally shoot an individual directly across the border as long as he did not know for certain that the victim had U.S. connections,” they argued.

The Supreme Court’s current term ends this month, and the border shooting cases will not be argued until this fall or next spring.

Calls seeking comment from Border Patrol and the union representing Border Patrol agents were not returned. But Joanna Williams, director of education and advocacy for Kino Border Initiative, said she hopes the final decision can prevent repeat cases.

“This is an opportunity that … might create accountability for others along the border and hopefully prevent future death,” Williams said. “And ensure that Border Patrol makes the necessary adjustments in order to have adequate training, accountability and even vetting in their hiring to ensure these shootings don’t continue.”