Every fall semester, students in Dr. Jacqueline Aitkenhead-Peterson’s Forensic Soil Science class got the dirt on learning how forensic scientists collected evidence from crime scenes.
The students received the experience in collecting soil samples and searching crime scenes for possible evidence during a mock crime scene investigation activity that is held outside the Heep Center each October. Petersen said that the activity is a major part of the course that revolves around a mock scenario called “Muddy Boots”.
The scenario involves a mock up story of a graduate student is reported missing and that all suspects in this case have to provide soils to a depth of 2.54-5.00 centimeters from their alibi location in the summer.
Each of the three sets of footwear recovered from the mock scenario either has these have either alibi location soil, reference soil or crime scene soil attached. The scenario also included having scattered remains, as well as other possible evidence items outside the north side of the Heep Center. The students had to process the scene in the same manner as taught to students of Law Enforcement at the Sam Houston State University’s Donor facility, Aitkenhead-Peterson said.
Students then collected and recorded evidence while soil samples are taken from several areas including the mock crime scene, the potential area of entry to the crime scene. The students also collected from reference soils, which Aitkenhead-Peterson said are various soils of the same soil series as the crime scene. The measurements were taken to a depth of 2.54 cm so they can serve as a comparison to soil that have been retrieved from footwear.
The students also used electrical conductivity meters to record how conductive the soil is in each grid square of the scene and also looked for hidden evidence items presumably belonging to the victim. She also said that wherever the conductivity is highest, there may be a potential cadaver decomposition island (CDI) where soil cores are taken to a depth of 15 cm as this depth is most useful for estimating post-mortem interval.
Peterson said that all the soils collected would be used for further chemical, statistical, and spectroscopic analyses to determine which pair of muddy boots was at the crime scene. The students then had to write a report on their findings.
Senior Forensics major Kaleigh Aaron enjoyed working the activity and that she loved the hands-on aspect of the class.
“I loved the fact that everything was hands-on,” she said. “It was very fun and I learned more with the hands-on than just with a lecture by itself. Doing the hands-on activities helps you to learn it better.”