Source: https://ncforensics.wordpress.com/category/drug-analysistoxicology/
Timestamp: 2019-04-19 16:31:51+00:00

Document:
The American Academy of Forensic Science Standards Board (ASB) has published ANSI/ASB Best Practice Recommendation 037, Guidelines for Opinions and Testimony in Forensic Toxicology, First Edition. This document delineates guidelines for best practices in forensic toxicology opinions and testimony, including human performance toxicology (e.g., driving under the influence of alcohol or drugs), postmortem forensic toxicology, court-ordered toxicology (e.g., probation and parole, drug courts, child services), and general forensic toxicology.
The American Academy of Forensic Sciences (AAFS) is working to develop best practice recommendations through a consensus process for each forensic discipline. Though the guidelines are non-binding, they do represent a deliberative process by which a group of forensic science practitioners, researchers, and court system stakeholders have developed recommendations on training standards, lab procedures, quality assurance, report writing, and testimony for each field.
…Standards and best practices create a professional environment that allows organizations and professions to create quality systems, policies, and procedures and maintain autonomy from vested interest groups. Standards ensure desirable characteristics of services and techniques such as quality, reliability, efficiency, and consistency among practitioners. Typically standards are enforced through systems of accreditation and certification, wherein independent examiners and auditors test and audit the performance, policies, and procedures of both laboratories and service providers.
The Guidelines specify that experts should provide both an analytical toxicology report and a separate report that conveys their opinions if they will offer an opinion on the interpretation of the toxicology findings (Section 4.1). In other words, under the Guidelines, an expert who will testify about the impairing effects of substances should provide that opinion in a written report, in addition to reporting the quantitative results that are typically provided in a Lab Report.
The Guidelines also define what are considered appropriate (Section 5.2) and inappropriate (Section 5.3) opinions and testimony by a toxicologist. These sections reiterate that opinions about impairment must be include consideration of the context of the case and not be based solely on a quantitative result. Also, words such as “scientific certainty” or “reasonable degree of scientific certainty” should not be used in testimony unless required by jurisdictional regulations.
All ASB publications can be downloaded for free from the Published Documents section of the ASB website.
Your client is charged with possession of marijuana. They tell you they possessed hemp – not marijuana. Industrial hemp is not visually distinguishable from illicit marijuana. Is that a defense? I would say yes, if your client is a licensed industrial hemp farmer growing industrial hemp in compliance with all regulations. But, if your client is not a licensed grower, the argument is less straightforward.
Cultivation of industrial hemp is now permitted as part of a pilot program in North Carolina. The program is permitted under federal law. The N.C. General Assembly enacted statutes governing industrial hemp and the N.C. Industrial Hemp Commission develops rules for the industry.
The N.C. General Statutes define “marijuana” as all parts of the plant of the genus Cannabis. However, mature stalks and sterilized seeds and their oils are exempted from the statutory definition of “marijuana.” See N.C. Gen. Stat. § 90-87(16). Also, for licensed farmers, cannabis sativa can be possessed and cultivated, so long it contains a delta-9 tetrahydrocannabinol (THC) concentration of not more than three-tenths of one percent (0.3%) on a dry weight basis. N.C. Gen. Stat. § 106-568.51.
Industrial hemp farmers use the stalks and seeds to make a variety of products that are legal for consumers to possess. Statute defines hemp products as “[a]ll products made from industrial hemp, including, but not limited to, cloth, cordage, fiber, food, fuel, paint, paper, particleboard, plastics, seed, seed meal and seed oil for consumption, and certified seed for cultivation if the seeds originate from industrial hemp varieties.” N.C. Gen. Stat. § 106-568.51. Presumably, under state law, it is lawful for consumers to possess these products because they are made from the part of the plant that is exempted from the statutory definition of marijuana; and, therefore both growers and consumers can possess them.
The amount of THC contained in these products is very low and these products are difficult to ingest in large amounts. For example, it would be impossible to ingest enough hemp rope to experience psychoactive effects.
Cannabis sativa leaves with low amounts of THC are a by-product of industrial hemp production. It’s not clear to me whether they have any industrial use in NC, though they can be used to produce cannabidiol (CBD) oil, which is a form of hemp extract which has no psychoactive effects and is used as a treatment for intractable epilepsy. Like the stalks and seeds, the leaves contain very low amounts of THC; and, like the stalks and seeds, it would not be possible to get high from ingesting the leaves.
Though the leaves of low-THC industrial hemp does not cause any psychoactive effect, they are not exempted from the statutory definition of marijuana and cannot be legally possessed by anyone other than a licensed hemp grower. See N.C. Gen. Stat. § 90-87(16). The only other exemption for a hemp product in the General Statues is an exemption for use or possession of hemp extract for certain medical purposes. See N.C. Gen. Stat. § 90-94.1.
So, if the leaves do not pose a public health threat, why is it illegal to possess them? One could argue that leaves that are visually identical to marijuana could be sold as a counterfeit controlled substance, so there is a public policy interest in their possession remaining illegal. However, given that these leaves are incapable of causing any psychoactive effects when ingested or consumed, from a public health perspective, it seems that possessing the leaves is as innocuous as possessing hemp rope. Given that low-THC Cannabis sativa leaves are not impairing or psychoactive, one could argue that a possession charge should be dismissed in the interest of justice. If the person is charged with the Class I felony for possession of marijuana, counsel could argue that the defendant should be allowed to plead to the Class 1 misdemeanor of tampering with an industrial hemp crop established by N.C. Gen. Stat. § 106-568.57 rather than the felony.
I’m interested to hear from readers about how courts have handled cases involving possession of hemp leaves as this is a new topic for me given the recent introduction of industrial hemp in North Carolina.
Blind studies and procedures are the gold standard of evaluating the quality and reliability of scientific results. Unfortunately, this has long been lacking in forensic science. Fortunately, strides are being made to introduce blind testing to forensics, most notably in the Houston Forensic Science Center (HFSC).
Currently, forensic scientists are tested periodically on their knowledge and ability through proficiency tests. However, scientists typically are aware they are completing a proficiency test and not case work. This allows for the Hawthorne effect to play a role in the testing, or the phenomena of a person behaving differently when they know they are being observed. Blind testing in forensic science will allow for blind samples to be included with case work in a manner that scientists cannot distinguish between a blind and a real case. This will help distinguish whether or not a laboratory adheres to guidelines and whether best practices are used in a day-to-day setting, as opposed to simply during an anticipated exam.
This article describes the efforts of Dr. Peter Stout, the HFSC’s chief executive officer (and former member of the NC Forensic Science Advisory Board), to implement a “blinds program.” So far, 329 blind samples have been integrated into normal casework in the firearms, toxicology, DNA, fingerprint, and digital forensic sections of the lab. In 2018, the lab plans to grow the program to 800 blind tests per year, or 5 percent of the lab’s workload.
Disguising a blind as a case sample is not a simple task, as the Forensic Magazine article describes. In addition to the challenge of creating a case submission that appears authentic, another particularly challenging aspect has been determining whether the blind samples could be searched in databases like AFIS, NIBIN, and CODIS.
At the HFSC, no errors have yet been reported in the testing of a blind. Use of blind tests will allow the lab to begin reporting error rates and confidence intervals, which will strengthen the testimony of analysts and allow them to answer questions about reliability of their work.
Would you like to learn more about how forensic toxicology testing is performed? Would you like to have a better understanding of how blood is tested for drugs or alcohol? Toxicologists Dr. Jay Gehlhausen and Dr. David Burrows will lead attorneys and investigators on a lab tour on April 27, 2018 in Wake Forest, NC at 10 am.
They will explain how blood and urine are tested for various substances, including through urine dip tests, immunoassay screening tests, and LC/MS-MS. Participants will be able to view the instruments and data and ask questions about the techniques used.
Attending a lab tour is a great way to improve your understanding of scientific evidence and its limitations. The tour and discussion will last about two hours. If you would like to attend, email Sarah.R.Olson@nccourts.org to sign up.
Any practitioner that handles driving while impaired charges knows the significance of field-sobriety tests (“FSTs”) to the investigation and prosecution of drunk driving. Scientific research supports the basic idea behind the tests — that test performance on FSTs is an indicator of alcohol impairment. What about when the impairing substance isn’t alcohol at all? Do FSTs remain relevant for marijuana impairment? That was the question before the Massachusetts Supreme Court in Commonwealth v. Gerhardt, 81 N.E.3d 751, 2017 (September 19, 2017).
Marijuana is legal for all purposes in the Massachusetts for adults 21 and older, but driving while impaired on the substance of course remains a crime. Some states where marijuana is legal have enacted drug limits for purposes of establishing impaired driving. Washington, for instance, has settled on a per se limit of 5 nanograms of THC (the primary active ingredient in marijuana) per milliliter of whole blood for drugged driving cases, similar to the .08 blood alcohol content limit for alcohol. In Colorado, that same amount of THC in the blood creates a permissive inference of impairment. The District of Columbia, by contrast, has a zero tolerance policy: any amount of the substance in the body is sufficient to be charged with drugged driving. Massachusetts, like North Carolina, has no per se limit for drugged driving when it comes to marijuana; the government has to prove impairment. A chemical analysis, by itself, will generally not suffice to prove impairment without a per se statutory limit. In cases where there is no statutory limit for the permissible amount of the impairing substance in the blood (or where there is no chemical analysis at all), officers often use FSTs to try to prove impairment, as they would in alcohol impairment cases. FSTs are therefore frequently substantial evidence in many (if not most) impaired driving prosecutions, regardless of the type of impairing substance. Gerhardt is one of the first cases to take a hard look at the use of FSTs in the context of a marijuana-only impaired driving prosecution.
Gerhardt was charged with Operating Under the Influence (the equivalent of NC’s DWI offense) after being stopped for failure to burn rear headlights. The officer reported smelling recently burned marijuana, and Gerhardt admitted he had smoked around three hours earlier. Gerhardt performed the HGN test, the Walk and Turn test, and the One-Leg Stand test, and other non-standard tests. He had no cues of impairment during the HGN test or the non-standard FSTs, but the officer detected several cues on the Walk and Turn and One-Leg Stand. Marijuana and paraphernalia were found in the vehicle as well. The Commonwealth sought to introduce evidence of Gerhardt’s performance on the FSTs and the officer’s interpretation of them. Gerhardt challenged the admissibility of that evidence under the Daubert expert-testimony standards.
The court began by observing that standard FSTs were “designed to detect alcohol impairment” and that they do so by “assess[ing] an individual’s balance, coordination, dexterity, ability to follow directions, and ability to focus on multiple subjects at the same time.” Id. at 756. The court noted that established scientific research supports the reliability of the tests in the context of alcohol impairment, but that the same was not true for marijuana: “A significant amount of research has shown that consumption of marijuana can impair the ability to drive. There is ongoing disagreement among scientists, however, as to whether the FSTs are indicative of marijuana impairment.” Id. at 757. The court cites several studies that demonstrate the conflicting research—some studies have found substantial correlation between FSTs and marijuana impairment; some have found no such correlation; yet others find correlation between certain FSTs and marijuana impairment, but not others.
That said, the court wasn’t inclined to rule the tests completely irrelevant. Noting that the bar for relevance is low: “To the extent they are relevant to establish a driver’s balance, coordination, mental acuity, and other skills required to safely operate a motor vehicle, FSTs are admissible at trial as observations of the police officer . . .” Id. at 751. Just like the officer can attest to observations of driving, the odors of the vehicle or driver, and the appearance and behavior of the driver, the officer can testify to what he observed during the FSTs as a lay witness. “That marijuana can cause impairment of skills necessary to driving . . . is within the common experience and knowledge of jurors.” Id. at 759.
However, the court placed considerable limits on the use of such testimony, given the status of the science surrounding the use of FSTs in this context. The officer may not testify to whether the test was passed or failed and cannot testify that the results of the FSTs show marijuana impairment. Such testimony “improperly implies that the FST is a definitive test of marijuana use or impairment.” Id. at 759-760. Further, the officer should not call FSTs in a marijuana impairment case “tests”, as that signifies to the fact-finder that the FST is scientifically valid for the purpose of detecting marijuana impairment. The FSTs in this context should be referred to only as “roadside assessments.” Id. at 760. Perhaps most importantly, the lack of a scientific correlation between marijuana impairment and a defendant’s performance on FSTs means that the FST results, standing alone, are insufficient evidence to sustain a conviction. “The fact that FSTs cannot be treated as scientific ‘tests’ of impairment means that evidence of performance on FSTs, alone, is not sufficient to support a finding that a defendant’s ability to drive was impaired due to the consumption of marijuana, and the jury must be so instructed.” Id. (emphasis added). The court attached to its opinion a proposed jury instruction tracking that mandate. Finally, the officer also cannot offer a lay opinion that the driver was “high” on marijuana (although an expert opinion would be admissible). Because the effects of marijuana on individuals vary significantly, and because there is a lack of scientific evidence demonstrating common signs of marijuana impairment, a lay opinion that a defendant was intoxicated due to marijuana consumption is improper.
So what’s the takeaway for practitioners? The case notes several studies on the connection between FSTs and marijuana impairment, which may be useful in a challenge to the use of FSTs in marijuana impairment cases. Because the studies are inconsistent, reference to them may support a finding that FSTs simply are not reliable in the context of marijuana impairment cases. Defense attorneys may point to Gerhardt as persuasive authority and argue for evidentiary limits on FST testimony in a marijuana impairment case similar to those imposed by the Gerhardt court, as well as for a similar jury instruction. Having the jury instructed on the fact that FSTs are not scientific evidence of impairment in this context would presumably be a powerful instruction. Likewise, preventing the officer from testifying that the defendant was impaired as a result of FST performance, that the defendant passed or failed the FSTs, that the officer’s lay opinion was that the person was impaired on marijuana, or from referencing the FSTs as “tests” at all, would be significant rulings in a DWI case with the potential to dramatically impact how the evidence of the case is presented to the finder of fact. When confronted with a marijuana-only impaired driving case, defense counsel is encouraged to consider filing a pretrial motion in limine addressing the expert testimony and relevance concerns of this evidence in the context of the case. The logic of Gerhardt may also support extending the same limitations to other impairing substances—where the scientific research does not conclusively link the defendant’s performance on FSTs to impairment on the substance at issue, there is a strong argument to be had that the testimony should be similarly limited.
Despite the ubiquitous nature of FSTs in impaired driving cases, their use in a non-alcohol impaired driving prosecution should not be accepted by the defense without a challenge seeking to properly contextualize their efficacy in this area. Further, even where the trial court allows the evidence over defense objection, many of the points that an attorney would raise in a voir dire hearing on the admissibility of FSTs would also go to the weight of that evidence before the jury. One can imagine a fruitful cross of the officer on many of the points raised in the opinion. We’ll have to wait and see how NC courts address these concerns. In the meantime, Gerhardt is an indication that FSTs are properly treated as having less probative value in a marijuana case than in the more-routine alcohol case, and that the defendant is entitled to certain protections limiting the way that evidence is presented, at least as long as the science remains uncertain.

References: § 90
 § 106
 § 106
 § 90
 § 90
 § 106
 v.