By Jon Herskovitz and Mica Rosenberg
(Reuters) - Relatives of a Mexican man they said was shot dead by U.S. agents on the Mexican side of the border in 2012 filed a lawsuit on Wednesday seeking $40 million damages from the United States for what the family claims was an excessive and illegal use of force.
Guillermo Arevalo Pedraza was shot from a Border Patrol boat on the Rio Grande River while his family was having a picnic on the Mexican side near Nuevo Laredo, the suit said. A lawyer for the plaintiffs said the amount of damages being sought was specified in a document filed separately.
Arevalo is one of at least 13 people killed under a Border Patrol policy the plaintiffs claim allowed U.S. agents to use lethal force to respond to rocks thrown their way if they feel the attack threatens their lives, the suit added.
"This institutionalized, systematic use of excessive, lethal force violated the U.S. Constitution, U.S.-ratified treaties, peremptory international norms, and our fundamental national values," the lawsuit filed in the U.S. District Court in the Southern District of Texas said.
The U.S. Customs and Border Patrol said the agency "cannot comment on pending litigation."
The suit claims Arevalo was having a family barbecue in a park on the riverbank and was shot twice by agents. He died in the arms of his wife.
A cell phone video purported to be of the incident shows the Border Patrol boat positioning itself near a group of people on the riverbank and then speeding away as several people rush to a slumped-over man.
At the time of the incident, Border Patrol said its agents were responding to rocks being thrown in their direction, Mexican officials said.
The suit said the boat had just encountered and harassed a man, not related to Arevalo's group, who was in the river trying to cross into the United States.
It said no one was throwing rocks and added: "Even if someone had thrown rocks at the agents, their response was grossly excessive."
Last month, the mother of a Mexican teenager she said was killed in 2012 in another cross-border shooting by U.S. Border Patrol agents filed a suit in U.S. District Court in Tucson seeking damages from the agency.
The suit filed in Texas on Wednesday is Civil Action No. 5:14-CV-00136.
(Reporting by Mica Rosenberg in New York; and Jon Herskovitz in Austin, Texas; Editing by Mohammad Zargham)