Forensic researchers aim to give weight to slivers of evidence

Chemistry majors Samantha Sierakowski ’19 (seated) and Timothy Kelly ’19 are spending the summer researching breakthrough methods in forensics.

Can a single thread found at a crime scene — or a fragment of wire found in the aftermath of a bomb explosion — be substantial evidence?

For six years, St. Olaf College summer researchers have been working to prove that the answer is “yes.”

Under the guidance of Professor of Chemistry and Department Chair Douglas Beussman ’92, student researchers Timothy Kelly ’19 and Samantha Sierakowski ’19 are working this summer to legitimize the practice of identifying single threads as meaningful evidence by using an isotope ratio mass spectrometer.

Timothy Kelly ’19 (front) and Samantha Sierakowski ’19 work with the isotope ratio mass spectrometer on a daily basis as part of their CURI research project. The necessary equipment takes up nearly an entire laboratory.

The isotope ratio mass spectrometer at St. Olaf, one of just a few in the nation at an undergraduate institution, measures the isotopes in a material. Any differences in the isotopes, which are elements that contain equal numbers of protons but different numbers of neutrons, can narrow the possible matches to a thread found at a crime scene or even the remnants of an improvised explosive device (IED) — and can help trace it back to the site of production and link a suspect with the crime scene.

St. Olaf researchers aim to prove the reliability of this technique to analyze evidence.

Their project is part of the college’s Collaborative Undergraduate Research and Inquiry (CURI) program, which provides opportunities for St. Olaf students from all academic disciplines to gain an in-depth understanding of a particular subject by working closely with a St. Olaf faculty member in a research framework.

Timothy Kelly '19 carefully places a sample into the mass spectrometer for analysis.
Timothy Kelly ’19 carefully places a sample into the mass spectrometer for analysis.

“This has been a really rewarding experience for me, to enter a project knowing very little about it, watch it come to fruition, and build upon people’s previous research,” Kelly says.

To identify a piece of material using the isotope ratio mass spectrometer, all investigators need is a piece of evidence the size of a crystal of salt. This summer the forensic team at St. Olaf is working to determine if the isotopes in electrical wires change after IED detonation. If not, they are one step closer to providing a course of action to connecting evidence to perpetrators.

“I’m looking to become a forensic scientist,” says Sierakowski, “and I would love if the research I was doing here was able to come more to life in the actual field.”

Samantha Sierakowski ’19 prepares a new sample for testing.

Beussman points out that in classroom labs, students are often working on lab assignments that have a nearly guaranteed outcome.

“But that’s not really the way science in the real world works,” Beussman says. “Being able to troubleshoot is a really important skill that is difficult to teach within academic labs. This summer research is really good post-St. Olaf training because this is what students will be doing once they leave here: solving problems, working on things, and not just doing things that work 95 percent of the time. You have to be somewhat comfortable with failure. It’s a mindset.”

After all of these trials and years of research, Beussman and his team of researchers are hoping to publish their findings by the end of the summer — and are hopeful that their work will give more weight to the single slivers of evidence found at crime scenes.

“I really like helping people and I can picture it being a really rewarding job,” Sierakowski says, “to speak to people who can’t speak anymore, and tell their stories, and give their families and friends closure.”