The Supreme Court on Monday sent a case involving the cross-border shooting of a Mexican teenager back to the 5th Circuit Court of Appeals -- leaving the question of whether the teen’s parents can sue the U.S. Border Patrol agent who shot him in the lower court’s hands.

“The facts alleged in the complaint depict a disturbing incident resulting in a heartbreaking loss of life,” the Supreme Court majority wrote. “Whether petitioners may recover damages for that loss of life in this suit depends on questions that are best answered by the Court of Appeals in the first instance.”

Justice Clarence Thomas dissented, and said he would have affirmed the lower court decision to dismiss the parents’ lawsuit.

The case – Hernandez v. Mesa – centers on the 2010 shooting death of 15-year-old Sergio Adrian Hernández Guereca, who was playing with friends in a cement culvert that separates El Paso, Texas, and Ciudad Juárez, Mexico.

In June 2010, Border Patrol Agent Jesus Mesa Jr., who was on U.S. soil, shot and killed Guereca, who was on Mexican soil.

The teen’s parents sought to sue the border agent in an American court for allegedly violating their son’s rights.

Hernández’s family argues that their son and his friends were simply playing a game in which they ran down the culvert from the Mexican side and up the American side to touch an 18-foot fence.

Mesa and the Justice Department argue that the agent was trying to stop "smugglers attempting an illegal border crossing" and fired his gun after he came under a barrage of rocks.

Had Hernández had been killed inside the United States, the case against Mesa could proceed. It would have also proceeded if he had been a U.S. citizen.

But the courts so far in Hernández’s case have said the Constitution’s power does not extend to people across the border or to those without a previous connection to the U.S.

What actually happened during the incident isn’t what the Supreme Court was asked to rule on. The justices were asked to decide whether to uphold the ruling of two lower federal courts that Hernández was killed by Mesa without any possible legal recourse for his parents or allow the border agent to be sued for damages for violating the boy's constitutional rights.

The details of the case have played out against the backdrop of President Trump’s repeated statements that he will construct a southern border wall and make Mexico pay for it.

The court also said Monday it would rehear a case that looks at whether immigrants detained by the government have the legal right to a bond hearing or to challenge their detention.

In that case, Alejandro Rodriguez, who came to the U.S. as a child and was employed as a dental assistant, was convicted of joyriding. He also pleaded guilty to misdemeanor possession of a controlled substance. He was then locked up for three years without the right to appear before a U.S. judge to ask for bond.

The American Civil Liberties Union filed a class-action lawsuit and won his release.

Fox News' Andrew O'Reilly contributed to this report.