TUCSON — Some evidence at the scene of an illegal immigrant shooting could have been tested to show the victim was holding a rock, according to a forensic scientist who testified at Border Patrol Agent Nicholas Corbett’s murder trial Wednesday in U.S. District Court.

Richard Watkins, a criminalist who is retired from a position at the city of Phoenix crime lab, said he conducted tests using the wool gloves worn by the victim, Francisco Dominguez-Rivera, as well as 10 rocks that were collected from the area.

During direct-examination by the defense, he explained he put on a glove, gripped each rock in his hand and then examined the rocks with a microscope. In each case, he determined, some amount of fibers from the glove were transferred to the rocks.

But, he said, some activity, such as dropping the rock, could brush off the fibers.

On cross-examination by the prosecution, he also acknowledged rain could wash away the fibers. According to the National Weather Service, it rained 0.04 of an inch that day. Watkins also acknowledged that if a person fell down and touched a rock, some fibers could be transferred even though the person never held the rock.

Watkins also disclosed that the defense paid him $235 per hour for working on this case.

Corbett is charged with second-degree murder, manslaughter and negligent homicide for killing Dominguez-Rivera on Jan. 12, 2007, near Naco. The defense rested Wednesday, and attorneys will give closing arguments today.

The defendant testified earlier this year that he acted in self-defense because Dominguez-Rivera tried to smash his skull with a rock. Corbett did not testify during this trial. Prosecutors, however, allege the shooting was unjustified because the victim was surrendering.

Randy Downer Jr., a private investigator in Tucson retained by the defense, also took the stand in court Wednesday. He said he went to the scene of the incident with the defense attorneys on Jan. 17 of this year and discovered two gloves on the ground. He collected them into evidence. The prosecution and defense later stipulated those gloves were worn by the victim.

The defense also called Wendy Adney, a Cochise County Sheriff’s Office detective who investigated the incident.

She acknowledged it is important to collect all pieces of evidence at a crime scene, including the rocks and gloves, and then figure out later if they are relevant to determine guilt or innocence.

Peter Hermansen Jr., a Border Patrol agent familiar with use of force policy, testified for the defense that Corbett would be justified in shooting Dominguez-Rivera if he were threatened with a rock during a close encounter. “If means, opportunity and intent are present, deadly force is authorized and warranted,” he said.

Robert Gilbert, chief patrol agent for the Border Patrol Tucson Sector, testified for the defense that he attended Corbett’s preliminary hearing in Bisbee in August and observed Oscar de la Torre, the Mexican consul in Douglas, make face and hand gestures in order to coach the three eyewitnesses on their testimony.

But Justice of the Peace David Morales, who presided over that hearing, testified he did not recall seeing any such signaling take place.

Outside the courthouse Wednesday morning, protesters gathered in support of both the defendant and the victim.

A group of about a dozen people supporting Corbett held American flags and signs stating messages such as “Mexico is the enemy” and “Save our nation, stop illegal immigration.”

John White, 55, of Tucson said he decided to attend the event because “it grieves me that our government won’t support our border guards who are doing their jobs.”

Nearby, another group of about 30 people came to honor the victim.

They held colorful flowers and sang songs, including one in Spanish written by Francisco Robles, a human rights promoter for Border Action Network in Tucson. “It is difficult to believe, but is the sad reality, how there are sick people, full of hatred and wickedness, that don’t know principles, much less dignity, what feeds their soul, are desires to murder,” they sang.

Herald/Review reporter Jonathon Shacat can be reached at 515-4693 or by e-mail at jonathon.shacat@bisbeereview.net.