The declaration was made as deputies continued to investigate the shooting death of a beloved nurse Philippa Ashford, who may have been hit by celebratory gunfire early New Year's Day.
On the heels of that case, ABC13 learned more about shell casings and how they can provide crucial evidence in these cases.
After the shooting, investigators went block by block looking for the shell casings, which the ATF said can provide important information in a case.
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"One of the challenges about finding or locating shell casings from a celebratory gunshot is, how far away is that gunshot. It could be a block away. It could be four blocks away," said Fred Milanowski, special agent in-charge at ATF Houston.
While the search continues, and if the shell casing is found, the ATF said it can be put into a machine, which takes 3D images of the casing. That's important because each shell casing is unique like a fingerprint. The images are put into a database called the National Integrated Ballistics Information Network, or NIBIN.
"So if a shell casing was recovered, that shell casing would be imaged and put in the database, and that would tell us if that firearm that was shot was used in any other crimes prior to that date," said Milanowski.
The data can also be helpful if the gun is used in a future crime. Last year, the NIBIN database helped close to 158 shooting investigations in the greater Houston area. Now, law enforcement hopes this case is a lesson to others.
"It's just absolutely irresponsible for people to shoot guns in the air," said Milanowski.
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