EL PASO, Texas -

A U.S. appeals court says a Mexican teenager killed by a Border Patrol agent was protected by the U.S. Constitution even though he was on Mexican soil.

The ruling Monday from the 5th U.S. Circuit Court of Appeals means the family of 15-year-old Sergio Adrian Hernandez Guereca can move forward with a $25 million lawsuit. The government may appeal the ruling.

U.S. District Judge David Briones had found that the family could not sue because the shooting's affects were "felt in Mexico." But the appeals court said that would allow agents to establish "zones of lawlessness."

Agent Jesus Mesa shot Hernandez in 2010 while trying arrest immigrants who crossed illegally into the United States. Mesa said he was attacked by rock throwers. Agents generally aren't allowed to shoot them.