A cooperative education program in forensic chemistry

Jun 3, 1983 - red smoke, under three different MS ionizing conditions are shown in Figure 7. .... educational program can all benefit from this intera...
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The ~hemiatryll'oxirulo~ Unit reported the reaulm of the eaamrnation of Molly Hmwn'~shoes. One of the shues was found to have some reddish smins on the sole. Slivers of thra portion of the sole were shaved off, extracted with solvent, and the extract analyzed by GCIMS. The analysis showed that the red stain on the shoe was the same chemical that is used to make the red smoke in the exploding dye packets. According to the examiner, this chemical is not widely used and it's quite unlikely for a person to have some on hisher shoes. [Authors' Note: Mass spectra obtained for methylaminoanthroquinone (MAAQ),the compound used to produce the red smoke, under three different MS ionizing conditions are shown in Figure 7. A comparison of the GCNS data from the shoe sample and a MAAQ standard showed the two to he identical.] The smudges on the victim's T-shirt were examined by GCNS in the Instrumental Analvsis Unit and were shown to he li~stickand base mnkeupottha same type used hy Molly Bnwn. I)isrrrpnnries betwren Ms. Hroum'a story nnd the results of the Laboratory's cxamination indicate r h n t Ms. Brown lied to the police in her statement. Friday,June 3,1983: In a follow-up inteniew with Ms. Brown, she insisted that her statement was completeand correct. When advised that laboratory tests linked her to the hank robbery through the handgun and the stained shoe, she changed her story. She said that Macumher came up behind her when she was talking to the police on the telephone and started "dubbing" her with the gun butt. She turned and was struck on the forehead. She grabbed the gun butt with both hands, they fell to the floor, struggled,and the gun discharged with hothof them holding it. When she ~~~~

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found that Mncumher had been killed, she panicked hreaur~she thought noone w d d helirve her story. She inked the suiridp hoping the inwstgatiun wouldn't go any further, and fled in her rar. She intentionally caused the car accident to explain her injuries. This version of Molly Brown's story fit all of the evidence: the lethal bullet was chemically linked to the handgun; both of their hands had eunshot residue: Brown could be considered as a wssihle source of the hair and bloid on the gun butt; and Brown f r d d be considered a possible wurrr of the blood and cosmetics m Macumber's T-shirt, which probably resulted from their ~truggle.As further evidence of her willingness to cooperate, she supplied the names of the two men with whom she robbed the hank. Friday, June 3, 1983: The information from Molly Brown was reported to SA Ted Grant at HQ. Since Macumber's contact may not he aware of his death, SA Grant was hopeful that the terrorist ring could he identified and arrested. He requested that the next set of instructions he intercepted and that a direct lead to the structure of the terrorist organization be developed. Please be advised again that the people and events described in this scenario are fictional, but the analytical techniques areuot. From this c&ealone i t should be obvious that many of the analytical techniques used required a high level of sophistication both on the part of the analyst and in the instrumentation used. The closine messaee arises both from the authors' exoerienre as analysts in the environmental field as well as the forensir field and from the u ~ i n i o n s~ r o v i d e dbv their manv colleagues a t the FBI witha& whos'help this &ticle would not have been possible: Advise your students who are planning careers involving chemical analysis to work for a solid degree in analytical chemistry. They can learn the forensic applications on the job but will have a difficult time getting the job without the basic chemistry skills.

A Cooperative Education Program in Forensic Chemistry Geoffrey Davles Northeastern Unlvwsihl Boston. MA 02115 Kathleen M. Hlgglns Northeastern University Boston, MA 02115

Figure 7. Identification of MAAQ by GCIMS. An unknown compound is generaliy consideredto be identified by GGIMS if me retenlion timeon the GC column matches that of the known standard compound run under the same conditions and if the mass spectrum matches that of the known standard. This figure shows the mess spectra of methylaminoanthroquinone (MAAQ. MW 237) under three different ionization conditions. The mass spectra are made up of either positive ions (positiveion chemical ionizatim-PIC!,and electron impactEl) or negative ions (negative ion chemical ionization-NICI), with the most abundant ions reflecting the unfragmented molecular ions due to resonance stabilization of the charge aver the anthraquinone ring structure.

A career in forensic chemistrv offers those students with a BS in chemistry opportunities for a rewarding application of their training. We describe a cooperative program for those wishing to pursue this profession that affords them an op~ o r t u n i t vto receive a Master of Science decree in forensic chemistri. T h e curriculum, outlined in ~ a b r e s1 and 2, has been in existence a t Northeastern Universitv since 1975. It covers all important aspects of the traininiand varied responsibilities of the modern criminalist, with some specialization, and has been found to be a successful program. The, courses are taken for the most part from existing offerings from a number of denartments a t the Universitv. T h e Drogram may be completed in a time span of roughly five academic auarters. One academic ouarter of that . oroeram is the " cooperative summer internship. After nine months of coursework the student's trainine is put to the test in the form of an unpaid internship in a working forensic science laboratory. The internship itself serves as an integral part of the overall educational process and provides real world contact and experience. It is our hope, of course, that the employer, the student, and the educational program can all benefit from this interaction. The student gets an opportunity to integrate analytical processes with the legal ones, a necessary step in professional Volume 62

Number 12 December 1985

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development. We regard this component as absolutely crucial to the preparation of effective practitioners and have found that field laboratories are eager to accept our student interns. Table 1. Full-Tlme Curriculum for MS Program In Forenslc Sclence FiRST YEAR Fall Quarter

R. E. Gaensslen Oepartmem of Forensic Science University of New Haven Wesl Haven, CT

Thomas A. Kublc Sciemiflc investigation Bureau Nassau County Police Departmem Mineola. NY

Peter J. Deslo

Modern Methods of Analysis Crime Scene Investigation Forensic Toxicology Criminal Justice Process

Department of Chemistry University of New Haven West Haven. CT

Henry C. Lee

Winter Quarter Forensic Materials Forensic Chemistry Techniques i Criminal Law Elective

Connecticut State Police Laboratory Meriden, CT

Spring Quarter Forensic Chemistry Technique I1 Arson. Explosives and Gunshot Residue Criminal Evidence Forensic Serology Summer Quarter in-Service Training SECOND YEAR Fall Quarter Master's Papero Seminar Computers in the Laboratory Forensic Serology I1(elective) or other elective Total Quarter Hours: (Minimum) 47 (Maximum) 51 'The Master's Paper ConstiMes s maja pall of me i i e r ' s s h m i c program. StMento may have wohedon researdlduringtheir acadsmio pmgram, but me paper may also resuit ham wor* m y undertook a.~ a n atheir f internsw It is not the s m e t v m of P r w m of research work namally auociated with an M S or PN) pmgram in chamisby

Table 2. Electlve Coursesa Studenls are required to take two additional courses hom the following list of electives Industrial Hygiene Analytical Separations Electroanaiyticai Chemistry I, I1 Optical Methods of Analysis I, I1 Advanced Organic Chemistry I. I1 Physical Organic Chemistry Polymer Chemistry I, 11. 111 Identification of Organic Compounds Functions of Human Systems Applications of Mass Spectrometry Victimology Women and the Criminal Justice System Science and Technology in Private Security Criminal Justice Planning and Dweiopment Directed Study in Forensic Chemistry Materials Science and EngineeringI, I1 Special Topics in Analytical Chemistry I. 11. 111 Spectrometric identification of Organic Compounds Isolation and identification of Nahrrai Products

Instrumentation and Analytical Methodology in Forenslc Science

concept^ in Pharmacology I. ii Concepts on Toxfcolagy I.ii Enu ronmenta Toxicology Pathology Drug Metabolism Advanced Medicinal Chemistry I. ii Advanced Clinical Chemistry I. 11 Pharmacology of h u g Dependence Biochemistw I. 11. 111 Forensic Serology I1 Cr8mtnal Procedures

Forensic analvsis eenerallv consists of three different components which may he employed in any given case.l.2 Identification refers to the qualitative determination of the identity of a substance, hased on measurements of its physical and chemical properties. Results of such identifications alone do not usually shed much new light on a case; however, there are cases in which the identification of a suhstance comoletes the forensic investieation. A controlled suhstance possession case is a good example of the latter. Not only is identification of the substance all that is reouired of the analyst, but also it is an essential legal requirement if the c h a r ~ eis to he sustained. Indiuidualization refers to the demonstration of common origin between two objects. At present, not many types of evidence can be completely individualized. A true individualization is a demonstration that a sample or item is unique within its own class or that questioned and known samples had a common origin. Reconstruction refers to the establishment of the place, time, and sequence of events that occurred during the perpetration of a criminal act. Complete forensic analysis consists of: (1) recognition of the physical evidence; (2) collection of the physical evidence, observing appropriate preservation and documentation procedures; (3) suhmission of the evidence for analysis; (4) aualysis of the evidence, which may involve identification andlor individualization procedures; (5) interpretation of the results of the examination in terms of the facts of the case; and ( 6 ) an attempt to reconstruct the events and present the results and conclusions to appropriate investigative and judicial bodies. Physical Evldence Because virtually any object or material can be relevant physical evidence in a given case, it is quite difficult t o arrive at a single, suitable classification for physical evidence. A simple classification scheme for such evidence and one that suffices for the present discussion is given in Table 1. A variety of different types of physical evidence is classified in the table according to whether it may be considered physical, chemical, or biological. The focus here is on instrumental methods of analysis, which are most applicable to the evidence classified as chemical or biological. Instrumental methods of analysis as applied to forensic science problems may be looked a t in two ways. One might attempt to categorize the types of evidence that are amena-

' Thornton, J. I., Lex ef Scienfia, 11, (1975).

DeForest, P. R., Gaensslen, R. E., and Lee. H. C., "Forensic Science. An Introduction to Criminalistics," McGraw-Hill. New York. 1983.

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Journal of Chemical Education