temperatures can reach as high as five hundred degrees Celsius. The Kelvin probe uses voltage to examine the surfaces where a fingerprint may have been deposited.’
‘So what you’re suggesting is that no matter what, you can’t wipe away a fingerprint.’
‘Exactly.’ He pressed a button on a small box attached to the probe. ‘Watch the monitor.’
Darby saw a magnified image of the bullet on the screen. ‘Looks like you’ve got something.’
Coop studied the faint, spidery lines of a partial latent fingerprint on the monitor.
‘I’m going to have to create what’s called a voltage map,’ he said. ‘It’s a three-dimensional rendering of the latent print. It will take a couple of hours. How’d the autopsy go?’
‘They’re doing it right now.’ Darby’s attention had shifted back to the hollow point lying on the dish.
‘Did you examine the body?’
She nodded, then said, ‘Would a scanning electron microscope destroy or alter the fingerprint in any way?’
‘No.’
‘Then before you do the voltage map, I want to borrow the bullet for a moment and take a closer look at the cartridge’s headstamp. It doesn’t look right.’
Coop, using tweezers, picked up the bullet for a closer look.
‘I don’t see anything unusual.’
She pointed to the round metal base. ‘The spark plug looks smaller than normal, don’t you think?’
He shrugged, then pushed his chair away from the table. ‘Go for it.’
23
Darby picked up the dish holding the bullet and carried it across the room to the lab’s brand-new scanning electron microscope. She loaded the cartridge into the chamber, shut the small door and then sat down, turning her attention to the console. Coop wheeled a chair next to hers.
The SEM’s terminal screen showed a magnified black-and-white image of the bullet’s headstamp. A thick white ring glowed in the middle, around the primer cap. Printed in the centre were two neat rows containing both letters and numbers:
GLK18
B4M6
‘What the hell is that?’ he asked. ‘Some sort of stamp?’
‘That’s exactly what it is.’ She printed off two copies of the image, then created a digital copy and sent the jpeg to her email. ‘What we’re looking at here is what’s being hailed as the latest technological advance in ballistics identification – microstamping.’
‘That technology hasn’t made its way into mass production.’
Darby nodded. ‘At the moment, the gun lobbyists have successfully prevented microstamping from seeing the light of day, but that may change soon. California is trying to push through a bill that would require microstamping to be implemented on all firearms over the next five years. If the bill gets passed, it’ll be the first state in the nation to have this.
‘Currently, we need to find the handgun and examine it to see if a particular bullet was fired through it. Microstamping eliminates that. It creates a ballistic fingerprint. A handgun’s firing pin is engraved with a unique microscopic code that stamps the gun’s make, model and serial number on the primer cap. The first row – in this case, GLK18 – is supposed to be the stamp for the handgun, the bottom row the code for the shop that sold it.’
‘So I’m assuming there’s going to be some sort of database that’ll store these numbers and codes.’
Darby nodded. ‘The database gives us not only the make and model of the handgun but where it was sold, who purchased it – everything.’ She worked the small joystick mounted on the keyboard in an effort to examine the edges of the cartridge’s headstamp. ‘And the database will also provide us with information about other crime scenes where cartridges with the same stamp were found. The beauty of this new technology is that you can see the stamp only through a scanning electron microscope.’
‘But since this technology isn’t in mass production yet, there’s no way we can trace it.’
‘This bullet has to be a part of a batch of test ammo.’
‘A prototype, in other words.’
‘Exactly. Only a handful of companies are doing microstamping, so this prototype or whatever it is should be easy to narrow down.’
‘The stamp on this first row here, GLK18,’ Coop said. ‘I’m guessing it’s a Glock eighteen.’
‘That would be my guess too.’
‘I’ve never heard of a model eighteen.’
‘That’s because they’re not sold here. It’s a military-issue weapon commissioned by the Austrian Counter- Terrorism Unit, EKO Cobra. As far as I know, they’re the only ones who use it. Take a look at the engraved letters around the headstamp.’
Coop put his arm around the back of her chair and leaned forward for a closer view. She could feel his arm touching her and was suddenly pierced by the thought of his moving away – not to another state but to another country.
‘R… E… and what looks like an S,’ he said.
She took a deep breath, trying to wash away the sinking feeling in her stomach. ‘There’s a company called Reynolds Engineering Systems that’s one of the leading developers of microstamping. They’re based in Washington, I think. Or Virginia.’
He turned to her. Their faces were inches apart.
‘How do you know all of this stuff?’
‘I do a lot of reading.’ She turned to the keyboard to print off more copies.
‘You need a hobby.’
‘This
‘They’re in Exam Room 2 working on the binoculars.’
‘What binoculars?’
‘Randy found a small pair of binoculars in the woods.’
Darby wondered if one of the men she had seen last night had accidently dropped them.
She stood up. ‘I’ll get on the horn and see what I can find out about this microstamp.’
‘Wait.’ Coop grabbed her wrist as she stood. ‘When you were examining Amy Hallcox’s body, did you see a tattoo?’
‘She had one above her left breast. A small heart.’
‘Did it have a black arrow through it?’
It did. ‘How did you know that?’
‘I need the fingerprint card for Amy Hallcox.’
‘It’s on the bench near the Kelvin probe.’
He walked across the room, grabbed the bag containing the Amy Hallcox fingerprint card and disappeared around the corner. Darby followed.
Coop stood at the last bench, his favourite spot, a small corner suite arranged around a grouping of windows that offered strong sunlight. Not today. The sky was black and heavy rain continued to pelt the windows.
He already had a fingerprint card set up on the bench. He slid Amy Hallcox’s card from the bag and examined it with a fingerprint magnifier. By the time she stepped up next to him, he had pushed the magnifier to the side.
‘It’s a match,’ he said, more to himself than to her.
‘A match to what?’
He slid a fingerprint card yellowed by age across the bench. She looked at the name typed at the top: KENDRA L. SHEPPARD. White female. No age or other information was listed.
