Forensics & Race - Teaching Diversity in a Physics Lab (Phys-111: Our Universe: Forensics Lab)

Gregory Braun, Ph.D.
Mentor: Ginger McKenzie, Ph.D. (Education)

Greg BraunAs the importance of diversity becomes more significant to the University's Jesuit mission, it becomes the responsibility of the faculty to address these issues in the classroom. Diversity is part of the Xavier University mission to "form our students intellectually, morally, and spiritually, with rigor and compassion, toward lives of solidarity, service, and success". Because physics attempts objectivity and detachment from society, this provides a challenge. But, the course Physics and Forensics offers a strong connection between science and society, and so is well-suited to adapting to teach social issues. I decided to look primarily at racial diversity, and hoped to show that the detachment from society provides science with an objectivity that serves to avoid the racial prejudices so common in our society. Through the process, I learned both what does and does not work well. While the overall student response was mediocre, I do believe that important issues were brought to the minds of the students. Within the limitations of the physics laboratory class, I am satisfied with the results of the project.

The course used was Phys 111, Our Universe: Forensics Lab, which we usually refer to as "Physics and Forensics". This is a core science class (the reason for the Our Universe denotation), taken by non-science majors to satisfy the sciences requirement. Many of the students choose this course because of some small interest in forensics, or at least in forensics-based television shows. Other students take the class only because it fits within their schedule. One criminal justice student has taken the course each of the last two semesters, but other than this the students have no dedication to the science of forensics. The course consists of lecture twice a week and lab once, with the lab broken into two sections. I taught both lab sections, and wanted to see what could be done to bring diversity issues to this part of the course.

The course teaches some of the methods used in forensics, but more importantly, teaches the science behind the methods. We want to show the students how scientists think and do things, rather than teaching them how to be forensic scientists. For our purposes, forensics is an example of an application of science. While the course topics include chemistry and biology in addition to physics, the focus is more on the nature of science itself, independent of any specific discipline. In the lab, we both practice these techniques and demonstrate the scientific processes that are involved. In some lab periods, we do not do anything that a forensic scientist would do, but instead deal with the phenomena that make the forensics possible.

The science of forensics is intrinsically linked to the criminal justice system, which has obvious racial issues. I wanted to look at how these racial issues affect how scientists must deal with certain techniques. When dealing with a population of unequal proportions, it is always important to be aware of how this will affect the science. For instance, while 12% of the U.S. population is black, they make up 41% of the prison population1. This tells us that whatever the cause, we can expect similar disparities in those involved in criminal investigations. We must learn how to deal with these inequalities and provide the most accurate results. This concern with accuracy is not just moral, but also scientific.

While I wanted to deal with racial diversity, I did not want to detract from the science in the class. In particular, I did not want this to become an ethics of technology course and debate the general use of forensics technology in the justice system. Rather, I want to look at specific ways in which race affects how we do forensics. Science still needs to be the focus of the course. So, while we mentioned the disparate treatment of different races, this was not the focus. Instead we focused on the extra thought needed by forensic scientists to prevent forensic evidence from contributing to this disparity. To this end, I discussed three topics involving racial issues, with increasing objectivity and reliability.

I must say that for the remaining weeks of lab we did not mention race at all. Some topics, such as fingerprinting or glass fragment analysis simply have no racial issues. I should also mention that we did not discuss the racial differences in victims of crime, for the simple reason that forensic evidence tends to deal much more with the perpetrator than the victim.

Course Topics Related to Diversity

The first lab dealing with diversity was the lab on eyewitness identification. Here we discussed two issues, the first being the differences in identification of people of different races. Race is one of the most distinguishing characteristics of a person, and the races are not equally represented in the population. Identification of an individual with any minority trait is different from that of a majority trait, whether the trait is race, height, or any other obvious physical descriptor. If an individual is described with a height of 6'8", this piece of information is of a different nature than that of someone 5'10". A person of extreme height is more easily identified, because fewer people are of that height; thus the height of this person carries more information than the height of a mediumsized person. The danger is that this one piece of information blinds us to other characteristics, if height is the only factor we consider. The same is true of race. If a suspect is identified as a black male in a predominately white population, then this fact eliminates a large number of people and so carries a good deal of information. If we use this to ignore other factors, however, then we run the high risk of identifying the wrong person. At the scientific level, we have to treat identification of a minority race, height, etc., as different from that of a majority trait.

This is an issue with any type of identification of any type of subject, but it becomes much more important when dealing with race. The fact is that the forensics techniques listed here may all discover the race of a suspect and nothing else. In a society that treats different races very differently, identifying a suspect by no more than their race can perpetuate stereotypes. In addition, this can lead to misidentification of innocent members of the same race. While any information is potentially useful to a scientist, this one piece of data can unfortunately strengthen the link in society's mind between race and crime.

The above effect is compounded by the fact that eyewitness identification is inherently subjective and unreliable. Whenever the judgment is being made by humans, personal prejudices are bound to interfere. And racial prejudices are some of the strongest, whatever those prejudices may be. We know that different races are not represented equally in the criminal justice system, whatever the cause. Finally, in addition to prejudices, any eyewitness identification is simply unreliable2.

The other issue we dealt with in the eyewitness identification lab is that of the Own-Race Bias, also called the "other race effect". Many studies over the years have shown that witnesses are about one and a half times more likely to make a mistake when identifying individuals of races other than their own2. While there are multiple theories for the reason behind this, our concern is the fact that it happens. As scientists, we would give less weight to interracial identification than to that of the same race, since it has shown to be less reliable. As a society, we have to consider the ramifications of determining the value of testimony based on race.

The next lab dealing with racial diversity was one in which we observed some identifying properties of hair. Here the students looked at hair under a microscope and learned what can be done to match samples. Looking at strands of hair alone can tell us only a few things, one of which is possibly race. Again we are faced with race being possibly all we know of a suspect, and many of the problems with eyewitness identification return. Hair identification is also somewhat subjective, and so personal prejudices again may interfere with the science. While far better than eyewitness identification, hair analysis does depend on judgment calls by the analyst. Here we are dealing with the prejudices of the forensic scientist instead of a general witness, and we may have more confidence in the objectivity of the professional scientist. This is the middle step in the theme of progressing objectivity of techniques, being more objective than eyewitness testimony, but less so than DNA. Also, hair analysis is more reliable than eyewitnesses, but less so than DNA. The FBI used DNA to investigate the accuracy of hair analysis and found 11% of positive hair matches to be false3.

Finally, we did a lab involving DNA. The actual lab itself dealt with beads showing the structure of DNA, as well as the steps taken to analyze it. However, at the beginning of the class we discussed some of the properties of DNA analysis related to race. The first thing I mentioned is that DNA has shown us there is no difference between races at the genetic level; there is no gene for "race." This leads to that fact that DNA evidence is not subject to some of the problems that other forensic techniques are. DNA analysis is much less affected by personal prejudices than are eyewitness and hair analysis. DNA is thus more color-blind, and it is this objectivity we value in a science. Here was a great opportunity to show that good science is less prone to personal prejudice.

We talked about using DNA to exonerate wrongly convicted suspects by groups such as the Innocence Project4. The statistics for these exonerations show that the racial makeup of those exonerated in general mirrors that of the prison population, which does not indicate or contraindicate any specific racial bias in the accuracy of convictions. The exception to this is if we look only at rape offenders, in which a disproportionate number of those exonerated are black. The significance of DNA exoneration to us was that it shows the unreliability of other, more subjective techniques. It is of note that false eyewitness identification played a part in 74% of the cases where the convicted was ultimately exonerated by DNA evidence5.

Usually, a DNA sample from a crime scene is matched to a sample taken from an individual. If there is no individual with whom to compare, the race of the DNA samples source may still be determined. While DNA does not show definitive differences between races, it can show traits that are more common in one racial gene pool than another. These markers can give a probable match for race. This technique is prone to error, and is also controversial6, and all of the earlier issues with knowing only a suspect's race remain problematic.

The Student Response

Laboratory classes are structured with an initial explanation and by the instructor, followed by the students performing the experiment or activity in pairs. The instructor helps individual groups during the entire period, but most of the presentation of material is done in the introductory lecture, and this is where most of my discussion of diversity occurred. The down side of this is that the students know that they are free to go upon completion of the experiment and so are eager to get started. This always makes student participation in the introductory lecture very limited, which is usually not a problem since they are participating throughout the lab. Since the diversity issues were dealt with primarily at the beginning of the class, student participation was limited. In future semesters, I hope to change this and involve diversity material throughout the lab period.

A note of interest is that, at the beginning of the eyewitness identification lab period, I asked the students to list some of the traits used to visually identify someone. I found it interesting that in both sections race was one of the very last things mentioned, after height, weights, scars, tattoos, etc. I think this represents a reluctance to think about race at all. This reluctance to bring up the issue is one of the things that I wanted to overcome.

At the end of the semester, we do a mock crime scene, where students and faculty were suspects in a staged crime. It happened by chance that in one section one of the students was identified as a black female by an eyewitness. I was very pleased when students brought up some of the issues we discussed at the very beginning of the semester. Although there was only one black student in the suspect pool (the other lab section), the students were quick to point out that this identification really had limited value in the case. Their discussion let me know that at least the few students working on this part of the case understood very well exactly what I had wanted to express upon them and remembered it months later.

When analyzing hair samples for the mock crime scene, the students first looked at the hair, and then chose students from a "mug book" from which to acquire hair samples for comparison. Some of the hairs found at the scene of the mock crime were of a very dark color, which led the students to request hair from students with dark hair, including the few black and Hispanic students. We talked about the effects of selecting members of one race for further analysis, and whether or not this was good science. Since the issue was purely hair color, the students determined that race was not much of an issue here. Hopefully, they understood that part of the scientific process is determining whether any factor is relevant, race or otherwise.

Near the end of the course, the class was assigned a short research paper on a topic showing the intersection of forensics and society. They were to look at some aspect of forensics that affected, or was affected by, not only those involved in the case but society at large. This could consist of looking at one specific case, a forensic technique, or some trend in forensics as a whole. While I expected many students would choose some diversity issue, only a few did so. Many students misunderstood the project, and failed to deal with any significant societal issue. Those that did deal with society covered interesting topics, but not many were diversity related. This may be partially due to the fact that students thought they needed to deal with something beyond what was done in the lab, and so they chose a topic other than diversity. Whatever the reason, I was disappointed that so few students did chose to further investigate diversity issues.

While the student response was less than I had expected, I am still glad that this material was introduced into the class. I do feel that the project was a success, and will continue to implement this material in the course. I hope that as I become more experienced in teaching this material, it may be better integrated into the lab experience as a whole, becoming a more central part of the labs in which it is involved.

When I started thinking about this project, I considered the possibility that this would be a candidate for the university's proposed diversity requirement. I have since reached the conclusion that this will not meet the requirements for such a course, at least as they are proposed now. The biggest issue is that there are only isolated topics which are relevant to diversity. The majority of the course (both lab and lecture) deal with scientific topics unrelated to diversity, and attempting to make diversity an underlying theme of the entire course would severely hinder the science. That being said, I think that the topics where race is a factor are very important, and need to be discussed. Whether or not Forensics fulfills a diversity requirement, I believe the university mission compels me to discuss these issues when they are relevant.


  1. Harrison, Paige M. and Beck, Allen J., Prisoners in 2005, Bureau of Justice Bulletin, http://www.ojp.usdoj. gov/bjs/pubalp2.htm#Prisoners
  2. Meissner, Christian A. and Brigham, John C., Thirty Years of Investigating the Own-Race Bias in Memory for Faces: A Meta-Analytic Review, Psychology, Public Policy, and Law, 2001, Vol. 7, No. 1, 3-35 10
  3. Saferstein, Richard. Criminalistics: An Introduction to Forensic Science. (8th ed.) Pearson Education Inc., Upper Saddle River, New Jersey, 2004.
  5. Rizer, Aurthur L., III, The Race Effect on Wrongful Convictions, William Mitchel Law Review, Vol. 29:3, 2003, p845-867.
  6. Cho, M. and Sankar, P., Nature Genetics Supplement, Vol. 36, No. 11, November 2004.

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Modern Physics in the Spirit of the Jesuit Tradition

Justin J. Link, Ph.D.
Mentor: David Mengel, Ph.D. (History)

Modern science has a tendency of being presented as the existence of facts found in nature. The pursuit of knowledge for the sake of the greater good is often not considered in the light of the search for fundamental truth. As technology continues to grow, impressively opening windows to new areas of research not previously realized, one must take into consideration the impact on society as a whole. It is here at Xavier University that we can create the environment that is "dedicated to engaging and forming students intellectually, morally and spiritually, with rigor and compassion, towards lives of solidarity, service and success." With the topics presented in Modern Physics, excellent opportunities arise to illustrate the ethical and moral implications inherent in this pursuit of knowledge.

Modern Physics (Phys 330 & 340) is a year-long course typically consisting of sophomore physics majors. The course addresses the important physical discoveries from 1890 to the present. Topics covered include Einstein's Special Relativity, Bohr's model of the hydrogen atom, quantum physics phenomena, radioactivity, nuclear reactions, high-energy physics, and fundamental particles. Due to the exponential growth of technological advances, there have been more breakthrough physical discoveries in the last century than there has been in previous millennia. The rigorous and ambitious objectives set in the course description truly limit the available time to have quality in-depth discussions concerning all of the moral repercussions involved in Modern Physics. As a result, the current international heated topic of nuclear power, both in electrical supply and weaponry, was the focus of our discussions.

Text books for the modern sciences thoroughly cover the scientific aspects of nuclear power but fail to address any moral implications, therefore, class discussions are included to increase the scope of the course. The time allotment for such discussions was originally set for one fifty minute class period. Due to the enthusiastic response from the students and excellent discussion, several class periods were required for the exercise. Before any such discussions began, the issue of respect was thoroughly emphasized due to the heated topics addressed. The students were also instructed to put themselves in the shoes of the scientists working on the projects, not as outsiders looking in. This point of view gained by such instruction lead to extremely insightful discussion. As the facilitator of the discussion, I played the role of devil's advocate trying to challenge the students to critically think about their comments in the discussion. It is with this challenge that the students appeared to dive deeper into the topics.

The first topic addressed was the use and control of nuclear energy. To begin the discussion, several challenging questions were posted for all to review and consider. The questions were as followed:

  • Is nuclear energy a safe and viable option?
  • What is the environmental impact of nuclear energy?
  • As nuclear power facilities reach their life expectancy, should they be allowed to continue to operate?
  • Would you want a nuclear power plant in your city?
  • Can nuclear power assist the socioeconomic status of troubled countries?

Can we responsibly supply the technology needed to these countries? These questions were not intended to inject my personal opinion, merely to ask the hard questions that the students must address and consider. Each question stimulated more in-depth responses but the attitude of the class changed significantly when discussing the last three questions. In order to have the students understand the significance of this topic, I introduced them to the nuclear facilities close to Xavier. Discussing facilities such as the Davis-Besse Power Plant in Toledo and the Perry nuclear power plants located in Cleveland illustrated that these issues are relevant to each and every student's lives. To bring the issue even closer to home, we discussed the history of the Zimmer Power plant and how it related to the mistakes made at Chernobyl and Three Mile Island. The implications of the new Piketon Nuclear Power Plant, which is only 90 miles away from Xavier University, were also discussed. The overall sentiment of the students was that nuclear power plants have an overall good effect but they didn't want them in their back yards.

The final two questions of the topic brought forth intriguing discussions. At the time of the discussions, the United Nations was attempting to control the Iranian procurement and control of nuclear enrichment facilities for the purpose of nuclear power and potentially weaponry. It became clear that most of the students had not critically thought about the implications or moral justifications for or against Iran obtaining the nuclear technology. Some students believed that the best solution was for the United States to build the facilities and control them at all costs. It soon became evident that this may not be a viable option and the complexity of the situation frustrated the students. This discussion was finalized at the end of the class period and nuclear weaponry was resumed in the following class.

The use and control of nuclear weaponry was the second topic addressed. To begin the discussion, three short video clips were shown to prepare the students for the discussion. The first two clips were that of the Nagasaki bomb explosion, and the released military video of the aftermath of the Hiroshima bombing. The final video clip was that of J. Robert Oppenheimer discussing the attitude of the scientists on the Manhattan project after the first successful test of a controlled nuclear explosion. These clips visibly upset the students and illustrated to them the severity of the nuclear weapon discussion. Just as before, the same discussion technique was used and the questions were as follows:

  • Do you, as a scientist, need to consider the moral implications of your scientific research?
  • Placing yourself in the shoes of the scientists of the Manhattan project, would you have completed the work on nuclear weapons?
  • Is the use of nuclear weapons necessary?
  • Do we still need to build more nuclear weapons?
  • Do other countries have a right to advance their nuclear weapon programs?
  • Do we have an obligation to share the technology with other countries?

These topics were by nature much more controversial and this fact showed in the discussions. The students quickly came to a heated discussion on the use of nuclear weapons and the building of the nuclear arms race. Being of the generation where the Cold War is something of the past and only discussed in text books, several students did not understand the need for the building of our own nuclear weapon stock pile. I personally found this rather eye-opening and was happy to hear the responses from other students. One student went as far as to research the topic and was happy to supply the class with several uncommon facts behind the fight for the first nuclear weapon. The last two questions introduced to the students once again challenged them to discuss the current events.At the end of the two-class exercise, the students were presented with two comments from the father of the Manhattan project J. Robert Oppenheimer. After the end of WWII, he stepped down from the nuclear arms program due to his moral convictions, and the project went on without him to develop the hydrogen bomb. I personally believe that these two statements truly brought home the message to the students.

"If you are a scientist you believe that it is good to find out how the world works; that it is good to find out what the realities are; that it is good to turn over to mankind at large the greatest possible power to control the world and to deal with it according to its lights and values."

"[W]e have made a thing, a most terrible weapon, that has altered abruptly and profoundly the nature of the world. We have made a thing that, by all standards of the world we grew up in, is an evil thing. And by doing so, by our participation in making it possible to make these things, we have raised again the question of whether science is good for man, of whether it is good to learn about the world, to try to understand it, to try to control it, to help give to the world of men increased insight, increased power. Because we are scientists, we must say an unalterable yes to these questions; it is our faith and our commitment, seldom made explicit, even more seldom challenged, that knowledge is a good in itself, knowledge and such power as must come with it."

By the end of the two-day discussion, several comments truly exhibited the significance of this effort. Student comments such as: "If we don't do it, who will?", "Who would be better to do the job than those who have morals and consider the ethical implication of the research" and "If we were in the shoes of those working on the Manhattan project, if we quit to demonstrate our vested interest in the nuclear weapons program, the program would still go on without us and those who continue the work may or may not consider the impact on society." These comments alone highlighted the importance and significance of our jobs as Xavier University professors to ask the hard and challenging questions to our students. These discussions emphasized the need for us to continue to be "dedicated forming students intellectually, morally and spiritually, with rigor and compassion, towards lives of solidarity, service and success." 


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