A South Texas judge said Friday he will take the weekend to consider whether a 17-year-old boy will stand trial as an adult for allegedly firing on a vehicle driven by a federal agent.

Hidalgo County District Judge Jesse Contreras said he was "puzzled" by the case of the boy who had no prior record and who a probation officer said was extremely compliant. At the end of arguments Friday, Contreras told attorneys he would offer his decision Jan. 29.

Authorities say the boy's father, Pedro Alvarado, woke up his 18-year-old son, Arnoldo Alvarado, and his then-16-year-old son last July and told them a suspicious vehicle was vehicle parked near their home. The boy and the two men are charged with the attempted murder of U.S. Immigration and Customs Enforcement agent Kelton Harrison. The boy is charged in state court, while the men are charged in federal court.

The state asked that the 17-year-old be tried as an adult. Prosecutor Marisela Ledesma argued that the seriousness of the offense and the boy's own admission that he grabbed his .22-caliber rifle warranted that he be tried as an adult.

Ricardo Flores, the boy's attorney, said it was a mistake made by a boy awakened in the middle of the night by his father.

Contreras dismissed that argument. "We're dealing with a sophisticated, mature individual," he said.

No one has suggested the boy knew a federal agent was inside the silver Jeep Grand Cherokee. Harrison was conducting surveillance in the area in a drug trafficking investigation. He was unarmed and fled at speeds of 100 mph.

The Alvarados followed in Pedro Alvarado's pickup truck.

The chase happened in the pre-dawn hours of July 3 in Hargill, a rural community northeast of Edinburg. Court documents indicate a related drug investigation had been under way for two years. Six others have been charged with drug offenses, but not the Alvarados.

At least one neighbor called sheriff's deputies to the area to investigate shortly before the confrontation and called Pedro Alvarado as well.

The younger brother fired the rifle from the pickup's back seat, while Arnoldo Alavardo fired a 9 mm handgun from the front, according to court documents.

The Alvarados chased Harrison for more than two miles until he crashed into a field.

Hidalgo County sheriff's deputy Joshua Kaltenbach testified Friday that Harrison heard vehicle doors slam after he crashed and believed it was the shooters. He ran into nearby woods and hid for about 15 minutes before returning to his vehicle. He had been shot once in the back, but recovered and transferred out of the area, Kaltenbach said.

Kaltenbach said when he asked the boy why they chased and shot at someone they didn't know, he replied that they had to. Asked why not call police to report the vehicle, the boy said, "We don't call the police." When authorities searched the home, they found marijuana, the guns and two illegal immigrants who did chores for the family.

Under questioning from Flores, Kaltenbach conceded Harrison could have turned on his unmarked vehicle's emergency lights to indicate he was law enforcement.

"This could have been avoided," if both sides had made different decisions, he said.