Protecting our borders has never been a more important security concern. The people tasks with doing just that recently coming under fire, accused of using compelsive force. Now the agency's top... See More
Protecting our borders has never been a more important security concern. The people tasks with doing just that recently coming under fire, accused of using compelsive force. Now the agency's top performer is showing us new tools that may help protect agents, mounting cameras everywhere along the border, including on agents themselves. ABC's senior national correspondent Jim AFL Avila gives us a rare look inside border patrol training. Reporter: You're watching the first videos ever seen outside of the government of a massive experiment by the U.S. Customs and border protection along America's borders. Reporter: For the last year border patrol agents have been testing different model body cameras. These cameras are the most controversial part of an 18-month retraining program for some 21,000 border agents, the largest federal agency to try them after a series of excessive force complaints, incidents like the beating and tasing of Aun status I don't Hernandes Rojas, caught on cell phone video. As he collapsed and died resisting deportation along the border in San Diego. The department of justice ruled the agents broke no laws and they did not prosecute. But not in this case. 16-year-old Jose Rodriguez. A Mexican citizen shot eight times in the shadow of the border fence that divides Nogales, Arizona, from Nogales, Mexico. The border patrol claimed he was thoughing rocks at the asian. Fusion unearthed a witness who claims the boy was not involved in the rock-throwing but instead was an innocent victim. Jose Carlos told fusion he saw two shots from two different places and no one from test government ever came to interview him. Last month a grand jury indicted the agent involved on murder charges. His trial is scheduled for January and he has pled not guilty. The southern border communities coalition, a watchdog group, claims 40 other ditz due to excessive force by border patrol since 2010. The amount of executeny, attention, and frankly the lack of being able to work with the public as a result of that increased suspicion that the agents are involved in excessive force. Reporter: Reform commissioner Gil kerlikowske says the shootings, all before his time on the job, harms his relationship with the community. He thinks cameras will vindicate the majority of his agents and hold accountable the overly aggressive. We've had almost 400 assaults on border patrol agents. Almost every single one of those in the southwest border. The body cams, how will they help your agents end violent situations? Most of the experience with body worn cameras in law enforcement has been that it has actually exonerated an agent or an officer, because it's one additional piece of evidence about what occurred. Reporter: The United States today spends more money on border control than ever before. More agents, more technology, more weapons. $18 billion a year, 8,700 hundred cameras watching the wall, watching the ports of entry. From helium balloons the terrain. And soon cameras on the agents themselves at a cost of tens of millions of dollars. There's one more, a total of five. I think in the long run with more cameras we'll prove that over and over again these agents treat people the way I've seen them treat people in a very humane way. We've had a relentless focus on tactics, on new policy, on equipment, on training, and body-worn cameras will be a part of that. Like this state the art simulator at a train facility where I experience firsthand how the experience can get out of hand. This is a colt m-4, one of the weapons we use. This is no different than any weapon you might find in the field other than it's being converted over with the laser kit. Reporter: First I'm confronted with a tragic movie theater active shooter scene. It requires quick response. And snap life and death judgments. In all, I managed to mistakenly shoot three civilians. I shot somebody bad. Reporter: Be shot at least twice myself. Before finally bringing down the gunman. This might be a once in a career experience, but the more we can expose them to these kinds of things the better for us. And the better for the public. Reporter: The next scenario was more akin to the everyday work of a border patrol agent. I'm given a rock to hide behind and attempt an arrest of smugglers at the border. We'd look at it as cover. I would hide and run, you would duck and cover. Fair enough, all right. Reporter: Border patrol agents trained with a less than lethal taser. Tase, tas, tas! What did you feel your body do? Just -- no control. You're tensed up. If it ever comes down to an encounter where I'm defending myself I'm going to use it. I know what the effects are. Reporter: Agents are also getting a new arsenal of less than lethal weapons. Our field commanders determine what tool best works in their aor -- Reporter: Like a wide variety of nonlethal bullets, pepper sprays, chemical sprays. We'll launch a bunch of projectiles either on the ground or infrastructure, on top of a fence maybe getting ready to throw rocks, we can hit the top of the fence with pepper balls, disperse pepper powder in the air, makes him cough, stop, get off the fence, get back. Reporter: In the past agents often responded to rocks with guns. Leading to fatalities and lawsuits. For Jose Rodriguez's mom, she says another tool that could change behavior would be to punish the man who kill the her son. And now awaits trial. Reporter: Life and death on the American frontier. And the man in charge who hopes new technology will make a difference. For "Nightline," I'm Jim Avila in McAllen, Texas.
This transcript has been automatically generated and may not be 100% accurate.