Guadalupe Guereca wants just one thing: ‘Justice.’

In a choked voice, the 59-year-old woman recounts the death of her teenage son, fatally shot on Mexican soil by an American policeman standing on the US side of the border.

‘He was taken away from me forever,’ the gray-haired mother said, sitting on the bed in her small home.

The killing of Sergio Hernandez Guerece will be examined by the US Supreme Court on Tuesday, coming at a time when President Donald Trump has called for building a border wall to keep out Mexican undesirables.

The shooting occurred June 7, 2010. The 15-year-old Hernandez was playing around with three friends in the dry riverbed of the Rio Grande that separates the Mexican city of Ciudad Juarez from its Texan neighbor El Paso.

The four friends were racing up the concrete embankment to touch the barbed-wire fence on the US side, and racing back down. The unmarked border line runs through the middle of the culvert.

Their game bothered Border Patrol agent Jesus Mesa, who managed to grab one of the troublemakers. He aimed his gun and fired, striking Hernandez in the head.

The teen died in Mexican territory, and the US justice system has so far prevented his family from suing the border agent in American courts.

Guereca described her son as a ‘very good’ boy, saying he was extremely attached to her as the youngest of her seven sons.

‘We were always very close,’ she explained, as her pale eyes filled with tears.

Two photographs of Hernandez, taken shortly before he was killed, are displayed on a dresser. They are the only photos that remain, she said, because her other children slowly removed the other ones so she's not constantly reminded of him.

But even now, more than six years after his death, she still takes out all of her son's clothes once a month and washes them.

Each week she visits his grave in the local cemetery, where brightly coloured flowers stand out amid the drab desert landscape.

 

- 'Viva Keko' -

She speaks to her son there, and asks him to take care of his brothers as well as two sisters who are living as illegal immigrants in the United States.

‘That's your assignment,’ she said.

Guereco worries about the impact of Trump's hardening immigration policies.

‘I hope he has a change of heart and will let them stay there,’ she said.

‘I am fighting for my son but also for other people who have suffered in similar cases,’ she said.

Hernandez's death is by no means the only one to have happened under similar circumstances.

According to Bob Hilliard, an attorney with Hilliard, Munoz, & Gonzales, the firm representing the Hernandez family before the Supreme Court, US border patrols have fatally shot at least eight Mexicans between 2006 and 2016 in cross-border incidents.

‘Losing in the Supreme Court and denying legal rights to Sergio's parents is practically giving the green light to massacre Mexicans,’ said Richard Boren, a volunteer from the Border Patrol Victims Network, based in the border city of Nogales, which supports the relatives of victims in similar incidents.

Under the bridge where trains pass between Cuidad Juarez and El Paso, a memorial to Hernandez is painted on a column.

‘Your mom and brother remember you,’ says a message inscribed on a blue cross marked with the date of his death. Another message refers to the teen by his nickname: ‘Viva Keko!’

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