A Hands-On Introduction to Forensic Science

Cracking the Case, Second Edition

Mark M. Okuda, Frank H. Stephenson, PhD.

• Éditeur: CRC Press
• Année: 2019
• ISBN:
  9781351023801
• Édition: 2
• Sujet: Derecho
• Sous-sujet: Derecho penal

A Hands-On Introduction to Forensic Science, Second Edition continues in the tradition of the first edition taking a wholly unique approach to teaching forensic science. Each chapter begins with a brief, fictional narrative that runs through the entire book; it is a crime fiction narrative that describes the interaction of a veteran homicide detective teamed with a criminalist and the journey they take together to solve a missing persons case. Step-by-step the book progressive reveals pieces of information about the crime, followed by the more traditional presentation of scientific principles and concepts on a given forensic topics. Each chapter concludes with a series of user friendly, cost effective, hands-on lab activities that provide the students the skills necessary to analyze the evidence presented in each chapters. The new edition is completely updated with special focus on new DNA techniques in DNA sequencing, DNA phenotyping, and bioinformatics.

Students will engage in solving a missing persons case by documenting the crime scene, analyzing physical evidence in the lab, and presenting findings in a mock trial setting. Within the chapters themselves, students learn about the technical, forensic concepts presented within each of the opening stories segments. The book culminates with having the students playing to role of the main characters in a trial—attorneys, scientific experts, suspect, judge, bailiff, and jury—to present and judge the evidence in a mock trial setting. The mock trial will mimic what takes place in a real courtroom, and the jury of swill be asked to deliberate on the evidence presented to determine the guilt or innocence of the suspect.

1

Crime Scene

Police Headquarters, Monday 9:12 AM

“Jenkins!”

His head pulled upright like that of an African gazelle when startled at a watering hole by the sound of a twig snapping accidentally under the paw of a stealthy predator. Maybe that was just a sneeze, he thought. Maybe. Alert, he strained to filter out the background din. Nothing. He went back to his reading.

“Jenkins!”

There it was again, but closer this time.

“Where’s Jenkins?”

He recognized that growl, and by its Doppler shift, it was coming up fast behind him. He jerked his heels off the wastebasket and yanked the steaming coffee mug from his lips, splashing a dose on the pages of his latest issue of True Detective, which he quickly flung shut and slipped under a stolen vehicle report. Lieutenant Robert Jenkins, swiftly wiping several fugitive doughnut crumbs from his chin, reeled his head around to see the department head, Captain Stan White, strutting down the path between the rows of desks littered with a dozen detective staff who were either tapping away on computer keyboards, talking prattle, or flipping through stacks of papers as they squeezed their telephones between ear and shoulder. They parted like cars on a two-lane road, yielding the right of way to a black and white, sirens blaring, as the captain barreled through them. They closed ranks behind him in his wake. Captain White cultivated a no-nonsense, tough-guy image and wore it tight to his skin like body armor. He downshifted as he approached Jenkins’ desk, and, as if he were a traffic cop flagging a commuter through an intersection, waved a manila folder in a southbound direction. “In my office, now!” he grumbled. Jenkins pried himself from his chair and merged a pace behind him.

Every time Jenkins stepped into the captain’s office, he felt as if he was trespassing the bounds of a mausoleum. It wasn’t decorated in a way that invites company or makes a soul feel cozy. Thin parallel layers of light sifting through the cracks of thick wooden blinds hanging like ribs against the windowpane etched a grate of glare and shadow across the opposite wall tiled in bronze plaques, framed certificates, and a collection of photographs picturing the captain shaking hands with a generation of mayors. A human skull stared vacant from the top of a filing cabinet, and the cadaver of a desiccated weeping figure collected dust in the back corner, a present, at one time, from his department to celebrate 20 years of service in law enforcement. Captain White dropped into a frayed armchair. As he lurched forward against a cluttered and scarred mahogany desk, his chair scratched along the linoleum like a lid sliding closed on a stone sarcophagus. He twisted the knob on the side of a banker’s lamp that then spilled light over a pile of forensic journals and glowed as green as kryptonite through the cover glass.

“What’s up, Captain?” Jenkins asked as he closed the door behind him, flicked the light switch on, and took up a standing position by the gallery wall.

The captain shot a brief but annoyed glance at the overhead light. “We’ve got, what we thought, is an unclaimed vehicle in impound, a white Subaru station wagon,” the captain replied, placing the fingers of his right hand lightly on the manila folder and skimming it back and forth across a small clearing on the top of his desk. “We were just about to sell it off on auction when Gonzales over in Motor Pool noticed a large stain on the cargo liner.”

“Blood?” Jenkins inquired, starting to feel a little like a dog being teased with a Frisbee.

“We don’t know yet.”

“How long has the car been back there?”

“That’s a problem,” the captain replied. “It’s been over six months. According to an inventory log, it was towed from Seaport Boulevard on January twenty-third.”

“And no one followed up? No one checked the registration?”

“Apparently, it fell through the cracks.”

“Any record of who may have had access to the vehicle since then?” Jenkins pressed.

“No.”

“And the towing company? Any record of who towed the vehicle?”

“Fell through the cracks,” the captain responded.

“Fell through the cracks?” Jenkins asked incredulously.

“Do you remember Sergeant Hayes?”

“Of course, he got transferred downtown to credit card fraud.”

“It was his case. When he left, it fell through the cracks.”

“But cases get reassigned,” Jenkins noted. “Yeah, it’s the responsibility of the department…er, ah, never mind Captain.”

Captain White glared up at Jenkins. “Anyway,” the captain continued, “I just had Henderson check it out. The vehicle’s registered to an Erica Holmes in the city.”

“Can she come get it? I hate to think of the accrued storage fee she’ll have to pay but at least she’ll have her car back and maybe we can get an explanation for the blood stain.”

“Again, now, we don’t know it’s blood, and, unfortunately, she can’t come claim it,” the captain replied.

“Why not?” Jenkins asked, cocking his head slightly like a puzzled beagle.

“We got a hit on a cross-reference. She’s a missing person.”

“This just keeps getting better,” Jenkins said, starting to salivate like one of Pavlov’s dogs. “How long has she been missing?”

“A report was filed on January twenty-fourth.”

“The day after her car was towed?”

“It seems so,” the captain responded. “Now, for the part you’re not going to like.”

“You’re giving the case to someone else?” Jenkins asked, deflated.

“No, I’m giving you the case, but you’re going to be working with a partner.” The captain seemed to brace himself for what he knew was coming.

Jenkins stood there for a moment and let his brain sift the particulates like a coffee filter. “A partner?” Jenkins asked skeptically. “Is this a disciplinary action? Captain, I can handle a missing person.”

“Bob,” the captain responded, his voice taking on an edge, “I’m tired of relying on the backlogged county lab. We’ve acquired the equipment, and we’ve hired someone to do DNA for us. She’s a graduate from Berkeley—a molecular biologist—and I want her to work with you on this one.”

“She’s fresh out of school?”

“Yep.”

“Oh, for Pete’s sake, Captain. Don’t saddle me with some wet-behind-the-ears rookie—some CSI wanna be! You can’t expect me to….”

“You’ll be fine,” the captain interrupted.

And there they were. Those three words: “You’ll be fine.” This was hardly the first time he’d heard them, and he knew they weren’t meant to reassure. But, rather, they were a demarcation—a line he didn’t dare cross. They were the signals that the discussion was over and that any further attempt to influence an outcome would be a waste of their times.

“Here’s the missing person’s report,” the captain said, handing Jenkins the manila folder. “Your partner’s name is Helen Chang. She’ll be meeting you at the Subaru in the back lot.” With that, the captain turned his attention to a stack of reports piled on the left side of his desk. “And Jenkins!” the captain said without looking up.

“Hmm?”

“The light!”

“Right, Captain,” Jenkins sighed, flipping the light switch off and stepping out of the office. He did not catch the captain’s glance again as he left the room, closing the door behind him.

Back at his desk, Jenkins lifted the metal case containing his crime scene evaluation equipment onto his desk and flicked the latches open. He verified its contents against his checklist:

Satisfied that all his equipment was in place, he headed through the gauntlet of detectives that cluttered his passage to the back of the building.

“Hey, Bob!” a rough voice called from his right. It was Detective Sanders. “Heard you have a new partner. Just be yourself there, buddy! If she bails on you, I win five bucks.”

“Was I the last person to know about this?” Jenkins sighed to himself, shaking his head slowly as he left the floor into the hallway.

Lieutenant Bob Jenkins had been a detective for close to a quarter of a century, and he’d seen it all, from the missing toddler he’d tracked down to the digestive system of a neighbor’s boa constrictor to the serial killer, the whack job from The Mission District, who dispatched his victims with a syringe full of Drain-O. (The press had dubbed that psycho “The Pipe Cleaner.”) The assaults, the kidnappings, the blackmailings, the murders.… Jenkins had come up against each one on that unsavory list. And every time he closed a file, every time he cracked a case, he gave credit to what he believed was his best crime-solving tool … his gut. He could feel a crime scene. Its color. Its texture. Its layout. Its smell. Everything told a story, and it was his gut that took it all in. It was his gut that nagged him to look in places that others on the force wouldn’t dream of. It was a feeling in his gut that had always led him to the bad guy. His gut spoke only to him. Jenkins worked alone.

But now, here he was, the guy they mockingly called a gumshoe and a maverick, getting partnered up. His gut began to churn. A partner, he thought. And a graduate from Berkeley! At least the tie-dye T-shirts have gone out of style. But she’ll probably have a tattoo on the small of her back, and her ears will be plugged into an iPod—someone consumed by the latest gizmos and gadgets. How am I going to make a criminalist out of someone like that! Solving crimes is about interrogating witnesses, chasing down leads, and crawling around the dirt inside the criminal mind. It’s about getting all that grunge hurled at you and trying not to let too much of it stick to your heart in a permanent way. She’d better at least be damn good with DNA.

Jenkins paced down the corridor toward the back impound lot, carrying his case in one hand and the manila folder in the other. He flipped the folder open with a downward snap of his wrist and read the missing person’s report. There, in the upper right-hand corner, was ...