The civil trial filed by a Mexican man who a U.S. Border Patrol agent shot in the desert of Southern Arizona began Monday.

In court documents Jesus Castro Romo’s attorney, William Risner, accused a Border Patrol agent of shooting Romo as he attempted to flee back toward Mexico.

“Our confident position is that this was not justified,” Risner said in his opening statements in the courtroom of Judge James A. Soto in U.S. District Court in Tucson.

A complaint Risner filed in January 2012 says an unnamed Border Patrol Agent on horseback intercepted a group of illegal aliens attempting to enter the United States west of Nogales. The agent, identified at trial Monday as Abel Canales, repeatedly struck Romo over the head with a lasso after Romo had surrendered.

The documents say Romo then fled because he “could no longer take the pain from the lasso hitting his scalp…” The agent then, according to the complaint, shot Romo, who collapsed to the desert floor.

Johanna Hamburger, with the U.S. Attorney’s Office for the District of Colorado, said Romo was shot as result of his own actions and failure to comply with law enforcement.

“This was the result of poor choices he made,” Hamburger said.

She said Romo was uncooperative with Border Patrol leaving Canales to fear for his own safety.

Hamburger said Romo had picked up a rock and motioned as if he planned to throw it at Canales.

The trial is scheduled to continue through the week.

Contact reporter Patrick McNamara at 573-4241 or On Twitter @pm929.