(WXYZ) - How does a case like this with so many different shootings come together?
7 Action News has learned the Oakland County Sheriff's Office crime lab played a key role in developing important evidence in the case.
The forensics experts at the lab stress that this was a team effort with the Michigan State Police crime lab and other agencies.
But 7 Action News has learned from other sources that two nine millimeter guns were taken as evidence from Raulie Casteel's house, and those weapons were brought the Oakland County lab for analysis.
Gunshots inside the lab help firearms examiners get to the bottom of cases like the I-96 corridor shootings.
The Forensic Science Laboratory at the Oakland County Sheriff's Office – where several pieces of key evidence in the case were analyzed.
Lab Supervisor Kent Gardner could not talk specifically about the shootings, but showed 7 Action News how bullets are scrutinized under a microscope to determine what kind of a gun was used in a crime.
"When a firearms examiner gets a bullet in, they'll look at the bullet, and see the impressions on the bearing surface of the bullet that represent the mirror image of the rifling in the barrel," Gardner told 7 Action News Investigator Heather Catallo.
Gardner says the markings on a bullet that occur after it's fired from a gun are kind of like fingerprints that can help forensic experts determine the make and model of a weapon.
"And then, by looking at those scratches, we call them serrations, you can arrive at an opinion whether that bullet was fired out of a particular firearm, to the exclusion of all other firearms," said Gardner.
In a case like this one – where 24 different shootings took place – Gardner says they make it a top priority.
"If it is a high profile or a case that really is a benefit to the public for us to work on it right away, we'll focus our resources on that," said Gardner.
The lab uses strict quality controls and always has a second firearms examiner double check the gun and bullet analysis.
For Gardner, it's challenging and detailed work – but rewarding.
"That's the nice part about the job, is being able to make an identification, and a link to a particular suspect," said Gardner.
None of the weapons or bullets that were shown as examples in our story were from the Casteel case.