Sunday, February 6, 2011

Session #1 Interview With Atty Dr. Frederic Whitehurst, On Forensic Identification of Cannabis

First off, I would like to thank Dr. Whitehurst for taking the time to explain his research with us.

 Frederic Whitehurst was a Supervisory Special Agent in the Federal Bureau of Investigation Laboratory from 1986 to 1998, where he went public as a  whistle blower to bring attention to procedural errors and misconduct.

FBI career

Dr. Whitehurst received a Ph.D. in chemistry from Duke University, a J.D. from Georgetown University and joined the FBI in 1982 and served as a Supervisory Special Agent in the FBI crime lab from 1986-1998.
While employed by the Federal Bureau of Investigation Laboratory, the FBI officially rated Dr. Whitehurst as the leading national and international expert in the science of explosives and explosives residue. He investigated, uncovered and reported scientific misconduct which forced the FBI crime lab to agree to forty major reforms, including undergoing an accreditation process. During this period, Whitehurst was forced to defend himself from retaliation by the FBI by hiring Kohn, Kohn & Colapinto, a Washington, D.C. law firm specializing in defending whistleblowers.

I am going to start off very basic, and eventually everything will tie in and hopefully you will see the bigger picture that we are trying to put out there.

KB - Dr. Whitehurst, is marijuana a plant?

Dr Whitehurst - Yes, 
This appears to be one of those "duh" questions, however we should start from the basics.

KB - What is a plant?

Dr. Whitehurst -  According to the American Heritage Dictionary of the English Language, American Heritage Publishing Company, Inc. 1975.
"Any organism of the vegetable kingdom, characteristically having cellulose cell walls, growing
by synthesis of inorganic substances, and lacking the power of locomotion."

At this point one must wonder how a police officer "identifies" marijuana without a forensic lab test.  Law enforcement officers carry guns, not microscopes.  Without a microscope one can not determine if the material has cells.  One can not also determine if the suspected marijuana grows by synthesis of inorganic substances.  Of course it lacks locomotion but so does road kill.  So how is it that an LEO even knows when he is looking at material in a little baggy that it is plant material?

KB -Does marijuana have leaves? If so, describe them?

Dr Whitehurst - The blade of the leaf is relatively thin and the principal veins form prominent ridges on the abaxial surface while the adaxial surface (that part of the leaf away from the central stem) is depressed into a groove above the vein. The cells of the upper epidermis are considerably larger than those of the lower and much more heavily cutinized (coated or impregnated with a waxlike, water-repellent material present in the walls of some plant cells, and forming a cuticle which covers the epidermis).

Stomata (one of the minute pores in the epidermis of a leaf or stem, through which gases and water vapor pass) are infrequent or lacking on the upper epidermis and very numerous in the lower one. Epidermal hairs are produced on both surfaces, being more numerous on the lower, and the large persistent hairs produce basal cystoliths. Glandular hairs also occur in large numbers, these being especially noticeable in the young leaf and less so in the mature blade, since they tend to break off with age.

Dr. Whitehurst- Can the law enforcement officer without a microscope then tell you that the green vegetable material he has is a plant and if he can, then can he describe the leaf structure of that plant as compared to the leaf structure of marijuana?  With so many species of plants on the planet how does he say that what he has is only marijuana and nothing else?  He can't.

Dr. Whitehurst- At this point we should realize that there are over 800,000 arrests per year in the US involving marijuana.  Approximately 80% of those are for possession for use.  Possession for use is not possession of growing plants.  The material that is being sold for use is ground up, not whole leaves, and maybe what some folks would feel are whole buds (flowers).  So, addressing the leaf particles first, can one answer the leaf architectural questions posed above without having whole leaves.  Well, of course not.  What we would be trying to do is akin to paleo-botany, attempting to determine the description/species of a plant from parts of the whole but not necessarily the whole leaf structure present.  Is a guess good enough in court? 

KB - Can we leave our analysis with an hypothesis that we have marijuana or do we need to test that hypothesis? 

Dr Whitehurst - Hopefully we would need to test the hypothesis before finding someone guilty of possession.   With only parts of the plant material present (assuming we have proven it to be plant material) have we got enough material for the law enforcement officer to say that it is marijuana?  
For over 70 years forensic laboratories have had to follow a protocol of microscopic and chemical analysis to "prove" the presence of marijuana.  So how is it that a police office is allowed to ignored that established protocol and simply state that he has marijuana, ignoring all the previous analytical practices.  The only reason I can imagine is that, for the most part, citizens have tired of the law and are ignoring it and creating huge numbers of criminal cases and forensic crime labs can not keep up with the overload.  So the standards have been lowered to the point of simply not carrying the burden of proof.  But that is just my hypothesis.

KillerBud - What about the bud?  Could we identify the marijuana from an analysis of the flowers?

Dr. Whitehurst - To do that we would ask ourselves what is a flower?  What are the parts of a flower?  Stamen, petals, pollen, pistils are all parts of flowers.  Simply purchase a 9th grade biology book from a used book dealer and see the questions that must be asked before one knows that something is a flower.  Try right now to draw a flower, a marijuana flower.  Show the stamen, the petals, the pistil, the anther, the parts of the flower.  Marijuana can be both male and female as well as a cross between the two.  So, officer, show me why you think this material is a marijuana flower.  And do any other plants have flowers that could be mistaken for marijuana flowers?  These are all questions that the normal police officer will probably not be able to answer. 

KB - So why does he think that what he has are marijuana buds? 

Dr Whitehurst- Invariably the answer will be smell.  What does marijuana smell like?  I have smelled a lot of marijuana both as a law enforcement officer and as a criminal defense attorney analyzing the materials found in the possession of my clients.  Who ever said that marijuana has a unique odor.  We'll deal with that at a later date, maybe tomorrow.

Can the law enforcement officer without a microscope then tell you that the green vegetable material he has is a plant and if he can, then can he describe the leaf structure of that plant as compared to the leaf structure of marijuana.  With so many species of plants on the planet how does he say that what he has is only marijuana and nothing else?  He can't. 

KB- Regarding expert witnesses, how would an drug test expert witness utilize forensic information such as this that you are explaining here?

Dr. Whitehurst -Unless you have the materials listed in the discovery request below you will not be able to determine if the testing laboratory work product is valid.  Once you have these materials you will need a drug testing expert to review and explain all of these materials.


                   Labatory Discovery: Controlled Substance

1. Evidence collection forms or logs (description of evidence, packaging, identification of
specimens, identification of individuals collecting samples, sample collection procedures).

2. Chain-of-custody records (field-to-lab transfers, and all transfers of evidence and associated
analytical samples within the laboratory).

3. Laboratory receiving records (records documenting the date, time and condition of receipt of
the evidence in question ; laboratory-assigned identifiers; storage location).

4. Laboratory procedures for subsampling (collection of analytical aliquots) and contamination

5. Copies of technical procedures in effect at the time the subject testing was performed (often
termed Standard Operating Procedures, or SOP’s) for each procedure used during sample
screening and confirmation, including; sample preparation, sample analysis, data reporting, and
instrument operation.

6. Copies of the two bracketing controlled substance proficiency results for each analyst and
technician responsible for preparation or analysis of subject specimens, including: raw data and
reported results, target values and acceptance ranges, performance scores, and all related

7. Copies of traceability documentation for standards and reference materials used during
analysis, including unique identifications, origins, dates of preparation and use, composition and
concentration of prepared materials, certifications or traceability records from suppliers, assigned
shelf lives and storage conditions.

8. Sample preparation records, including dates and conditions of preparation, responsible analyst,
procedural reference, purity, concentration and origins of solvents, reagents, and control
materials prepared and used, samples processed concurrently, extract volume.

9. Copies of bench notes, log books, and any other records pertaining to case samples or
instruments; records documenting observations, notations, or measurements regarding case

10. Instrument run log with identification of all standards, reference materials, sample blanks,
rinses, and controls analyzed during the day/shift with subject samples (as appropriate: run
sequence, origins, times of analysis and aborted run sequences).

11. Record of instrument operating conditions and criteria for variables, including as appropriate:
GC column, instrument file identification, tuning criteria, instrument performance check (e.g ion
abundance criteria), initial calibration, continuing calibration checks, calibration verification.

12. Record of instrument maintenance status and activities for instruments used in subject
testing, documenting routine and as-needed maintenance activities in the weeks surrounding
subject testing.

13. Raw data for the complete measurement sequence (opening and closing quality control
included) that includes the subject samples. For GC-MS analysis, this would include: areas and
retention times, injection volumes, dilution factors, chromatograms and mass spectra. As
prepared and as determined values for all quality control samples.

14. A description of the library used for spectral matches for the purpose of qualitative
identification of controlled substances, including source(s) and number of reference spectra.

15. Copy of records documenting computation of the laboratory’s theoretical production yield,
including the basis for the computation, and the algorithm used, as appropriate.

16. Procedure(s) for operation and calibration checks of analytical balances used to weigh
controlled substances.

17. Results of calibration checks and documentation of mass traceability for gravimetric

18. Results of contamination control surveys for trace level analytes relevant to test methods at
the time of analysis, including sampling design and analytical procedures.

19. Records and results of internal reviews of subject data.

20. Method validation records documenting the laboratory’s performance characteristics for
qualitative identification and quantitative determinations of the controlled substance, to include
data documenting specificity, accuracy, precision, linearity, and method detection limits.

21. Copy of the laboratory’s Quality Manual in effect at the time the subject samples were tested
as well as the laboratory’s most recent Quality Manual (however named; the document that
describes the laboratory’s quality objects and policies).

22. Copy of the laboratory’s technical or operational procedures in effect at the time the subject
samples were tested (often termed Standard Operating Procedures, for analytical laboratory
operations) as well as the laboratory’s most recent technical or operational procedures for
analytes detected in subject samples.

23. Copy of the laboratory’s ASCLD-LAB application for accreditation, and most recent Annual
Accreditation Review Report, as appropriate.

24. Statement of qualifications of each analyst and/or technician responsible for processing case
samples to include all names, locations and jurisdictions of cases in which these personnel
testified concerning the same substances found in the present case.

25. Copy of the laboratory’s ASCLD-LAB on-site inspection report, as appropriate, as well as
any reports of on-site inspections by any other testing laboratory audit organization.

26. Copy of internal audit reports generated during the period subject samples were tested.

27. List of capital instrumentation in the laboratory at the time subject testing was performed,
including manufacturer, model number, and major accessories.

28. Production throughput data for the drug testing section: numbers of tests performed per
month or per year, and the number of Full Time Equivalent personnel in the drug testing section
of the laboratory


  1. If you read this new series and would like to follow up with a question regarding this subject to Dr Whitehurst, feel free to leave a comment!

  2. Holy cow! Can't wait to talk with him on


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