Jose Manuel Marino-Najera had been walking through the desert with a bundle of marijuana on his back for three days when he ran out of water. The 31-year-old father of one had been working on a grape harvest in Caborca, a border city on the Mexican side of the Sonoran Desert, when he found out about an opportunity to get to New York. He had an uncle there and, hopefully, would find work. Crossing the border illegally, with the help of coyotes, or smugglers, is typically a very expensive endeavor. But Marino had found a group willing to help him make his way north free of charge. In fact, they would pay him if he made it. All he had to do was carry a backpack filled with marijuana across the border with him.

Marino and the others in his group, all of them hauling marijuana on their backs, had made it to the Arizona side of the desert through an undesignated port of entry when they decided to stop. Dehydrated and feeling weary, Marino lay down beside another migrant under a tree and fell asleep. When he awoke, his arm was allegedly being mauled by a Border Patrol dog.

All of these details are according to a claim filed against the United States by Marino in federal court last week. The claim says that two Border Patrol agents and a canine approached a member of Marino’s group at around 7 a.m. on June 21, 2013. The agent handling the canine unleashed him to sniff the man’s backpack, and the dog scratched and barked, indicating there were drugs inside, the claim says. As the agents apprehended and detained the man, the dog remained unleashed, and ran down the hill to where Marino was sleeping. Marino says that the Border Patrol agents ignored his cries for help, allowing the dog to maul his arm for several minutes before putting the canine back on the leash. The claim states that the man who had already been detained could see the dog biting Marino’s arm from where he and the agents were standing, and could hear Marino crying for help.

Because the Border Patrol agent handling the canine was acting within his duties as an employee of a federal government agency, Marino’s suit argues, the United States is liable for damages, including medical expenses, lost income, severe pain, and emotional suffering caused by the dog bites.

“When you’re in this country, the Constitution applies to you,” Bill Risner, Marino’s attorney, told The Daily Beast. “He can sue under the same circumstances that a U.S. citizen can sue if they’re mistreated.”

As a Tucson-based personal-injury lawyer, Risner frequently encounters cases involving Mexican nationals who have been shot, injured, or otherwise mistreated by U.S. Border Patrol agents. He said he currently has three Border Patrol shooting cases pending, including one in which his client was allegedly shot in the back four times by a Border Patrol agent. He survived, Risner says, but was left permanently injured by a bullet to his spine.

“The Border Patrol is taught to kill people,” Risner said. “I guess the word sort of gets out that I’m not afraid to sue them.”

That’s why, after a representative from the Mexican consulate met with Marino, who was ultimately apprehended and detained in Arizona for a brief period, the consulate referred his case to Risner.

A Border Patrol spokesperson was unable to comment on this case. But while reporting on the overlap between the Mexican drug and human-smuggling industries earlier this year, a public information officer for the Border Patrol’s Tucson sector explained that many desperate migrants, unable to pay the thousands of dollars demanded by smugglers to cross the mostly cartel-controlled U.S.-Mexico border, find themselves faced with carrying a marijuana-filled backpack through the desert as their best or only option.

“The guy was harmless. To come up [north], this is what he did,” Risner said, referring to Marino’s backpack. “To let the dog chew on him and chew on him when he’s screaming, that’s wrong.”

Whether or not Risner will be able to convince a federal judge that the U.S. should be held responsible, is another story. He may not be afraid to sue, but Risner said the real difficulty of a case like Marino’s is that both his client and the eyewitness (the man who was apprehended while Marino was being bitten by the dog) are living in Mexico.

“Keeping in contact with those people, and mechanically getting them to the trial, those are the hard parts,” Risner said.

When asked whether he was optimistic about Marino’s chances of success based on previous cases, Risner replied: “Well, I’m willing to do it.”

“I really only file these things when I think we’ve got a good chance of getting a recovery, or when it’s outrageous enough that it really ought to be brought to a judge,” Risner said. “To me, this one is outrageous.”