Department of Public Safety investigators are confident they have the man connected to at least four of the shootings along Interstate 10 in Phoenix.
The big break made with the help of information coming from a Phoenix pawn shop.
"It is surprising to think anyone would commit an act like this and then go to a pawn shop," said Bradley Garrett, former FBI Agent and Criminal Investigations expert.
But according to the Department of Public Safety, Leslie Merritt, Jr. did go to the shop soon after the first four shootings along I-10.
Pawn shops turn over all information on the items they receive at the end of the day. So with the serial number from the gun and Merritt’s information, it was handed over to the police the same day the gun was pawned.
The ballistics were a match and that was enough for an arrest. But it might not be enough for a conviction.
"You still have to put him at the scene and prove he was the one that actually used the weapon," said Garrett.
So now, investigators are working to develop a timeline and technology will play a critical role.
They will rely on cell phone towers to help track the suspect.
"If he placed a call two minutes before the second shooting, where was he?" said Garrett.
Depending on Merritt’s location, it could help or hurt DPS’s case. License plate readers could also place his car near the area of each shooting.
All circumstantial evidence that potentially makes the case stronger, but still doesn’t guarantee he’ll be convicted.
"You have to convince the jury beyond a reasonable doubt that you have the right guy,” said Garrett.