Some headline grabbing crimes: a shooting on the greenway, a violent robbery at a neighborhood store, and a shooting spree that leaves holes throughout an apartment complex.
The common thread, no matter what the crime- the evidence, ends up at The Western Lab.
"Our job is to apply science to the law. We are unbiased. We apply it to either side of the law - the defense or prosecution. Our job is to find the truth," explains Kevin Patrick.
Patrick is the director here, overseeing more than 50-employees as they analyze swabs, test drugs, match markings and compare fingerprints.
This lab receives evidence from 144-different state, local and federal agencies.
"We average between 80-100 cases a day is what comes into the laboratory from our jurisdictions," he says. "That's a lot," says the reporter. He agrees, "That is a lot. Statewide, we end up about 60-thousand, 60 to 63-thousand cases a year."
It's painstaking and important work.
One slip up could mean an innocent man is jailed or a guilty man, freed.
"What we do is pretty important we believe, and we want to make sure we get it right and we want to take the time we need to get it right," says Patrick.
Balancing that with the needs of the police department and court system can be challenging especially during active, high profile cases like the recent Schewels' shooting.
Explains Patrick, "To give you an example, 15-minutes before you got here Roanoke City was here turning in that evidence, and I was having that discussion with them about what was available, what they had, what they wanted, what they were looking for, so we've already screened it and it's already in the system."
While cases like that grab headlines, the majority of the lab's time is spent on processing drugs.
Patrick estimates those cases make up nearly 90-percent of the work load.
But, help is on the way, construction has started on a 63-thousand square foot addition.
It will give the department more space, room for new equipment and area for training facilities.
It could also enable the lab to add scientists to tackle more cases.
The 40-million dollar construction project is expected to be completed in 2016.
It will also give the medical examiner's office more room, as well.