Since the shootings happened overnight, it's hard for investigators to find shell casings in the dark, Osburg said. And, with a 42% increase in homicides last year, investigators don't have the manpower to door knock for clues in shootings where no one was hurt.
Instead, Osburg visits the next day with his canine that's trained to alert authorities to 19,000 different compounds of explosives.
On a recent morning, 13 Investigates joined Osburg as the dog sniffed two intersections and a grassy field, searching for shell casings that can be matched to previous crimes.
"On its face, it seems like it's not that important, but when you find a shell casing it could potentially lead to something bigger down the road," said Osburg. "A neighbor may have seen who shot today and give that information to police. They may not have known about the murder that occurred with the same firearm down the block."
Despite the increase in homicides and violent crime, HPD still has the same number of officers on staff.
Three years ago, HPD and other local agencies joined the newly-formed ATF Crime Gun Strike Force, which uses teamwork and high tech that links guns to bullets to crime scenes and shooters. The federal collaboration also means aggressive prosecution gets Houston's most violent criminals off the streets for good.
ATF Special Agent in charge Fred Milanowski said in federal cases, there's no monetary bond. If there's strong evidence the alleged suspect is a risk to the community or they are a flight risk, the individual is detained prior to trial.
"We know that shooters don't just stop after one shooting. And we know that the first shooting is hard. The second one gets a little easier. And by the third one, they quit thinking about it and they're just pulling out the gun every time they're upset, whether they're shooting at a car or a person or a house," Milanowski said. "Our mantra is, let's get shooters off the street before they become homicide suspects."
Over the last two years, the strike force has connected suspects to 466 violent crimes.
"I know that in Houston everyone's concerned, as we are, with the homicide numbers going up, but I can tell you that if there were 466 more criminals out there doing bad things with guns, it would be worse," Milanowski said.
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In one case, three people were arrested as part of a crew that robbed GameStop, grocery stores and money transfer kiosks. Federal court records show they first started with just threatening victims with a gun, but eventually shooting victims over time.
HPD Lt. Cathy Richards said investigators linked the three suspects, and 26 others, to 39 robberies from Galveston to Beaumont and beyond. This spring, the most serious crew member was sentenced to nearly 27 years in federal prison.
Richards said local police department officers who are part of the collaboration are sworn in as task force officers and can file federal charges.
"The defendants are staying in jail longer," Richards said. "When we file these federal charges, the crimes literally stop because the defendants are in custody and the consequences are a lot higher."
The federal charges also mean concerns over low bonds and COVID-19 era slowdowns in state court just don't apply.
"We want people to know that there are consequences to your actions and that if you're going to go and be reckless and shoot someone, just even shooting guns in the air, things like that, that is reckless and very dangerous for our citizens," Richards said. "When we can do these charges like this and put these guys behind for a long period of time, I know it's making the citizens feel safe."
In another case, task force officers were able to connect spent cartridges from four aggravated robberies from Montgomery County to Harris County and Houston over a period of three months. Then, officers linked a fourth, but still did not know the shooter. From there, old-fashioned police work and victim interviews along with the high-tech firearm analysis allowed investigators to link a suspect. Once arrested, ATF documents reveal the suspected shooter, Brandon Ruffin, gave a confession. He was sentenced to 18 years in state prison.
Calls for shots fired 'astronomical'
It's important for ATF to respond to the victimless shootings HPD can't thoroughly investigate because even if no one is injured, Osburg said every bullet fired from a weapon leaves behind unique clues that investigators are using to catch violent crime suspects.
"The amount of calls coming in for just shots fired is just astronomical," Osburg said.
The spent cartridges that are left behind after a bullet is fired have a unique pattern it leaves behind on shell casings.
The casings are photographed on a microscopic level and the details are entered into NIBIN, a national Bureau of Alcohol, Tobacco, Firearms, and Explosives database. That information is then compared to other cartridges within the area, and gives investigators leads that can help connect the weapon to a crime committed weeks ago or miles away. Ultimately, if a suspect is known in any of those cases that information can be used as evidence to link them to previous crimes where they're either the suspect or know who previously used the gun in a shooting.
"It's finding the needle in a haystack sometimes," Osburg said.
Still, law enforcement says the effort is worth it because police are running from call to call, with little time for proactive policing.
Newly-sworn Houston Police Chief Troy Finner said he's meeting with federal partners and hopes stronger collaborations with other agencies will help lower violent crime.
"(With) the limited staff that we have, we better be making sure that we're laser-focused on those individuals who are committing the violent crime," Finner told 13 Investigates' Ted Oberg in late March. "All of us agreed that there's going to be a laser focus on those individuals, those gang members, or those individuals who are pulling the trigger, shooting and killing people. We're going to go after them and we're going to go as a team now."
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Aggravated robberies were up 32% in 2020, compared to 2019, according to a 13 Investigates analysis of HPD crime data. More than 19,300 aggravated assaults were reported in 2020.
Richards said in the last two and a half years, 216 people were arrested for aggravated robbery as part of the task force. More video enhancement software, and overtime or staff to work more shootings would help.
"We could probably work even more if we had more people, more officers," Richards said. "We're not even hitting it."
WATCH: Inside HPD's high-tech collaboration arresting hundreds
High-tech tool 'doesn't go to sleep'
HPD is also relying on a pilot ShotSpotter program, which is a high-tech gun detection system that alerts law enforcement officers seconds after someone pulls the trigger.
So far in Houston, HPD Commander Milton Martin said the system is beating 911 callers in speed and accuracy.
"When you have officers rolling up on a gunfire incident and the shooter is still standing there with the gun in their hand, having not had a chance to put the gun away and run, that actually convinced the officers about the viability of the tool," Martin said.
In the first four months of this year, the system alerted officers to more than 2,500 shots fired within a five-square-mile area in southeast Houston, where the ShotSpotter sensors are placed, Martin said.
The technology has been used across the U.S. for years, but just started in Houston on December 28. Most of the 2,500 shooting incidents it detected were cases where Houstonians didn't even call 911.
"It doesn't go to sleep. It doesn't take a day off and it's listening to all the time for gunfire," Martin said. "What we're seeing is in the realm of 90-plus percent of the gunfire that's detected is never called in by anyone, whether it is because they've become numb to gunfire in the area, or because they don't really think there's anything the police can do because (they) don't know exactly where it happened."
For the few instances where residents did call 911 to report gunfire in the area where the ShotSpotter sensors are set up, Martin said the information got to officers two minutes faster. The technology also provides a 25-meter radius of where the shots fire may have occurred.
"It is able to narrow it down to a house. It is able to narrow it down to the backyard of a house. It can narrow it down to a specific part of an apartment complex. It's a very accurate system," Martin said.
The system itself has actually detected over 20,000 incidents of "impulse noise" which could be gunfire. Through checks and balances, officers were alerted to only 2,500 of the cases where the system believed it was gunfire.
Martin said the system doesn't record people's conversations, but instead listens for gunfire. Once gunfire is detected, it sends an audio recording of the shots fired to officers along with the location in real-time.
Since the start of the year, HPD made 17 arrests using the system, including seizing 15 guns, three of which were stolen. That means less than one percent of the 2,500 gunfire calls resulted in an arrest.
Still, Martin said they will continue to use the software for a full year, with the hopes that there will be funding available to keep the software.
"I see it as a very viable tool to have in our toolbox to help us in addressing gun crime," Martin said. "Even without a citizen's call, they're able to go directly to that location, not only look for potential suspects, but also evidence of gunfire."
Milanowski said allowing multiple agencies to partner together means they have access to each other's resources and ultimately can use different technology to solve crime.
"If you stand still, you're going to get run over," he said. "Criminals are evolving, so we have to evolve."
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