CASE #1   Starbucks Stick-Up

“This is a robbery! Everybody down!”

While students moved through the Natural Science Center’s lounge area en route to a classroom, these words rang out as a figure brandishing a weapon ran up to the counter at the building’s snack area.  Students did as they were told and the person fled, turning around a corner out of sight from the participants.  Suddenly, shots rang out.

Directed by Jill Shelley of the Department of Political Science and Criminal Justice, ,the students were instructed to make use of the law enforcement officer’s primary and most valuable weapon: observation.  Students took notes immediately after the incident on the person’s description, the surroundings, the time.  They questioned the victim, Leslie Ogle of the Starbucks shop.  They searched for evidence —fabric scraps from a jacket (the suspect’s?), and shell casings found in a corridor (did it have fingerprints?) [Note: In reality, blanks were used in this enactment and the weapon was fired into a police-approved “safe box.”]

In the computer lab, the students worked in pairs at computers with a software package, FACES 3.O, which allowed them to perform a facial composite much like a sketch artist would.  They were guided in the use of this program by Dr. Brad Bielski of Thomas More College.  The program has the ability to morph together numerous characteristics selected independently from a list of possibilities such as head shapes, hair styles and colors, eyes, lips, and students could make adjustments on the basis of memory.

As they completed their composite sketches,  a new development in the case was announced. Two suspects in handcuffs were escorted into the room by Sgt. Jay Baker, Officer Dave Tobergte, and Officer Charles Millbaugh (who shared the duty) from NKU’s Department of Public Safety. 

Both suspects were female, similarly dressed, and close in build and physical description.  Although the keen-eyed investigators agreed on the description, both suspects had plausible alibis.  Were they perps or just in the wrong place at the wrong time?  The investigation had to go to the next level: who fired the gun?

Science answered the question.  When a firearm is discharged, primer residue is ejected and contains particles that may land on the shooters, hand, arm, or clothing.  Scanning electron microscopy (SEM) is used to determine the presence, size, shape, and chemical composition of the particles.   Science this residue is fragile, the investigators had to act fast,  using cotton swabs to remove residues from the suspects’ hands, an analysis was done at NKU’s SEM lab under the direction of Cynthia Cain of the Department of Biological Sciences. The suspect was identified from eyewitness description, and the police sketch, and her use of a weapon was verified through SEM. The rest would be up to the courts.

CASE #2   The Unkindest Cut

The team of investigators was called in.  As a preliminary precaution,  police tape blocked entry for all but authorized personnel.  What was known so far was this: A faculty member was missing.  His office was in disarray.  His week’s schedule was posted in red dry-erase marker,  but he missed appointments.  A red pen lay on the desk.  A quantity of paper towels were in the trash; unused ones still on a shelf.  Red smears about the office might be ink — or they might not.  And a bloody knife was on the desk.  But was the case as  –ahem– cut and dried as it appeared?

Once again, students started this exercise with  observations, noting  furniture, materials in the room, positions of these things, indications of schedules, and, of course, those bothersome smears.  A serious concern was if the substance was, indeed, blood.  Enter science and Dr. Vern Hicks of the Department of Chemistry to answer the question.

Dr. Hicks demonstrated the use of luminol to determine the presence of blood.   Luminol undergoes a chemiluminescent reaction due to the iron in hemoglobin, producing a light that can be detected with the human eye.  As the student investigators sprayed the luminol in the darkened room, they discovered blood not only on the obvious areas but in unexpected places as well.  The luminol test is very sensitive and can be used successfully on surfaces and fabrics that have been washed to remove visible traces of blood. [Note:  Because blood can be a medium for the transfer of many serious diseases, sterilized sheep blood was used for this demonstration.]  Chemiluminescence and other forms of energy transfer involving light were demonstrated in this activity.

The next step in the investigation was to determine the origins of the blood.  The knife’s owner came forward but denied any wrong-doing.  He maintained he had been hunting and the knife was used merely as a utility tool.  It had been inadvertently left in an office he was visiting.  

Student investigators worked with Dr. Ray Richmond of the Department of Biological Sciences to compare the blood found at the scene with that on the knife.  Using DNA fingerprinting, students saw how DNA segments are distributed in unique fashions and how these segments appeared different from individual to individual.  Armed with this knowledge, they were able to conclude there was an extremely high probability that the blood on the knife was different from that at the scene.  Although the mythical faculty member is still “missing,” the owner of the knife was cleared of suspicion.

CASE #3  Here’s Looking at You

A body was found face down on the floor, fallen from a chair.  A bottled beverage sat on a table nearby, along with a letter written in bold black ink.  The words were sad, those of a jilted and despondent sweetheart.  Could it be suicide — or was that a cover for something more insidious?  Mark Marsolais of the Department of Political Science and Criminal Justice guided investigators through the observations at the scene.

From the criminal investigation standpoint, one troubling aspect of the case was the document.  It might questionable, and students learned about preserving documents, examining them against other samples written by the same person,  and other techniques.  In addition to comparisons, the possibility of forged or altered writing had to be considered and the investigators entered the realm of chromatography and chemistry, led by Dr. Vinay Kumar. 

Chromatography is an analytical technique used for the separation and identification of components in a mixture.  Forensic scientists use chromatography to determine whether a document contains two or more different inks.  In the activity students used paper chromatography to determine whether the document at the scene was written with one or two ink pens.  In the demonstrations, students also learned that other mixtures (such as food colorings, dyes, etc,) can be separated by chromatography.

A tenet of investigation states that every death with no visible signs of trauma must be considered a poisoning until the facts prove otherwise.  Although homicides as a result of poisoning are much rarer than suicides or accidents, all possibilities had to be considered in this case, and attention turned to the beverage bottle.  Again, chemistry played a key role in the investigation. Methanol, ethanol, and propanol are alcohols with one, two, and three carbon atoms, respectively.  Ethanol is used in alcoholic beverages, methanol is toxic, and propanol can cause digestive difficulties. Nuclear Magnetic Resonance (NMR) is used to identify all three.  Dr. Vern Hicks showed students the operation of the NMR and the spectrum obtained for analysis along with cyroscopic activities with liquid nitrogen.

The clues in this case varied from team to team so students would not know in advance what outcome to expect.  In one scenario, it was determined that the note was genuine and the death was intentional.  In the other, the note proved to have been written with two different pens and that methanol had been surreptitiously added to the beverage.  In a word:  murder.

Case #4 Collision Course

Not all investigations the students undertook involved murder or mayhem.  An important facet of many investigations is reconstruction of a scene and with the use of NKU’s facilities, this was able to occur on a miniature scale.

The scene was one investigators (not only police detectives but insurance investigators and engineers) study daily:  a traffic accident, its causes, and results.

In the exercise devised by Dr. John Filaseta and Dr. Scott Nutter of the Department of Physics and Geology,  students looked into the occurrence of a truck broadsiding a car in an intersection.  The mystery to be solved:  Was the truck speeding before it hit the car?

Two exercises helped to solve the problem.  The students discussed 1) the effect of friction and 2) the amount of force needed to cause an object to move and then lose motion.  The started by finding a means of measuring the actual force needed to slow an object down given its weight. Student investigators, guided by Drs. Filaseta and Nutter, were able to apply the principle that total mass times velocity is momentum, and then computed the friction (as evidenced by tread marks reported at the scene) to estimate the speed of the truck before it hit the car.  Students were given the weight of the vehicles and, using the air tracks and weights in a physics lab, were able to test their conclusions.  They also learned the lesson that algebra also has an important place in crime-solving.

The teams of student investigators worked on a different case each day, and on the last day of the camp had prepared posters for an open house that detailed their activities for the week.  They had additional opportunities to learn about the use of science in from several representatives from the local law enforcement community.  Lt. Col Jeff Martin,  assistant chief of Northern Kentucky University’s Department of Public Safety, discussed his work in a high-profile murder case during his service with the Boone County, Kentucky police force.  Stuart Oehrle of the Department of Chemistry, who spoke on the identification of explosive materials.  Dr. Greg Dahlem, Department of Biological Sciences, gave an outdoor presentation/demonstration on flesh-eating flies and the role of forensic entomology in crime investigations.  Susan Vanlandingham of the Kentucky State Police Crime Lab explained the use of lab work in the identification of illegal substances.  Two members from the Hamilton County Police Department gave demonstrations on fingerprinting and other methods of evidence detection at crime scenes.  Kenton County, Kentucky Police Detective Tim Scheidt explained the finer points of accident reconstruction.

The success of the Middle School Forensic Camp is unquestionable.

“The students had a great time,” said Dr. Phillip H. Schmidt, NKU-CSI “chief”and CINSAM director.  “They learned how to apply the scientific method to crime solving: formulate a question; make observations, collect data; analyze data; make a conclusion and present it.

“Beyond that, they enjoyed a challenge.  It was great fun and it also made them think.” 

He added that the participants had an opportunity to gain a wide range of experiences involving many different scientific applications, learn methods of investigation from top teachers and university faculty members, and use equipment to which most middle- and high school students and even many undergraduate students do not have access.

“What made it even better was that the participating teachers were challenged, too,” Dr. Schmidt added.  “They learned how to bring interesting information and activities into their classroom and ways of instructing students in the scientific method.  Everybody learned.”

Case closed.

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