LRC Comments to ASTM E2548-11

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COMMENTS BY THE OSAC LEGAL 

RESOURCE COMMITTEE (LRC)

TO: Seized Drugs subcommittee of the Chemistry-Instrumental SAC

FROM: Christopher J. Plourd, Chair, OSAC Legal Resource Committee (LRC)

RE: OSAC LEGAL RESOURCE COMMITTEE (LRC) COMMENTS ON:

E2548-11 “Standard Guide for Sampling Seized Drugs for Qualitative and 

Quantitative Analysis” (hereinafter referred to as “E2548-11”).

Response from the Seized Drugs Subcommittee

The OSAC Seized Drugs subcommittee recognizes and appreciates the comments received from 

the Legal Resource Committee (LRC) pertaining ASTM E2548-11, Standard Guide for Sampling 

Seized Drugs for Qualitative and Quantitative Analysis. The following responses attempt to 

address and clarify some of the issues brought to our attention by the LRC.

The document in review (E2548-11) was original published by ASTM in 2007. The document 

was originally published as Part IIIA of the Scientific Working Group for the Analysis of Seized 

Drugs (SWGDRUG) Recommendations, which are intended to assist forensic analysts and 

managers in the development of analytical techniques, protocols and policies. The SWGDRUG 

Recommendations are internationally recognized as minimum standards that may be 

supplemented to address unique jurisdictional laboratory requirements. 

The document under consideration is neither a test method nor a prescriptive standard. 

Therefore, many of the comments provided by the LRC members are not considered applicable. 

Also, this document is not intended to encompass all other related standards, terminology, 

validation documentation, etc. that may assist in its application. The field of seized drug 

analysis is an extensive one encompassing the subjects of sampling, chemical identification, 

presumptive and confirmatory analytical techniques, method validation, quantitative procedures, 

structure elucidation, measurement uncertainty, reporting protocols, and many others. It is 

unrealistic and impractical to attempt to include all these subjects into one single document, as 

the result would be an ineffective standard that would not be useful for practitioners. Efforts are 

already underway to address some of the aforementioned subjects via the publication of separate 

documents on the OSAC Registry.
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There appears to be some misconceptions and misunderstandings regarding the OSAC process 

as well as the process in use by the standard development organization (SDO) under which this 

standard is published (ASTM). We believe that it would be useful to provide additional training 

regarding these procedures to not only members of the LRC but also members of other resource 

committees and individual discipline subcommittees.

We understand the desire for these documents to be written such that they are more 

comprehensible to lawyers and judges. However, many of these documents under review have 

already been in the forensic community for over ten years and they were originally drafted with 

the goal of providing useful minimum standards for seized drug analysts. In fact, there are many 

seized drug laboratories throughout the world that use this document (as well as the SWGDRUG 

Recommendations) as a foundation for their policies and procedures. It is our strong belief that 

attorneys and judges have the ability to consult scientists in order to interpret a scientific 

document, much in the same way as a scientist would consult an attorney to interpret a legal 

document. Serious consideration is being given to all the comments provided by the LRC 

members. However, we believe that making significant changes to the document in order to 

address the resource committee’s would take away too much from the original technical and 

scientific intent of the document.

The Seized Drugs subcommittee of the Chemistry-Instrumental SAC is proposing to 

approve an existing ASTM E2548-11 standard to the OSAC Repository registry.

Our comments are primarily intended to enhance the value of the Standard to the legal 

community. This Standard will be most helpful if it not only helps assure high quality 

results in the laboratory, but also is written to show how work performed in accordance 

with the Standard is both well grounded in theory and data and that it is presented 

within the boundaries of “the knowledge and experience of [the expert’s] discipline.”1

Consequently, the comments are intended to address four questions that are important 

to the legal reception of the Standard: (1) Is the Standard written as clearly as possible, 

and without undefined technical terms and symbols, so as to enable lawyers and judges 

to grasp the main ideas and requirements set forth? (2) Does the Standard describe in 

detail how the peer-reviewed and readily available scientific literature establishes the 

validity of the assumptions underlying the scientific tests and the interpretation of test 

results? (3) Does the Standard list the limitations of the tests and results and provide for 

expressions of the uncertainties in measurements and inferences drawn from them? (4) 

Does the Standard include recommendations or requirements for the creation and 

retention of documentation of the test and the contents of reports, including the scientific 

limitations of the tests and related conclusions or inferences? These are matters of both 

 

1 Kumho Tire Co. v. Carmichael, 526 U.S. 137, 148 (1999) (quoting Daubert v. Merrell Dow Pharms, Inc., 

509 U.S. 579, 592 (1993)).
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technical merit and legal importance. Although the LRC is not able to assess the 

scientific merit of a Standard, our review encompasses whether a Standard makes a 

prima facie case for the validity of the methods and legal utility of the kinds of expert 

opinions that a Standard contemplates.

_________________________________________________

Comment by LRC member David Kaye:

Comments of David Kaye on Placing ASTM E 2548−11 (“Standard Guide for Sampling 

Seized Drugs for Qualitative and Quantitative Analysis”) on the OSAC Repository of 

Standards and Guidelines.

The document is not ready for inclusion as an OSAC Standard. According to the 

QIC PowerPoint presentation of July 27, 2015, OSAC-approved documentary standards 

and guidelines are to “have demonstrated: Technical merit; Detailed Scope; Fitness for 

purpose; Uncertainty measurement and potential bias; and Method validation, as 

appropriate.” A “standard ... specifies uniform methods, actions, practices, or processes, 

protocols. Compliance [is] mandatory and modified only under unusual circumstances.” 

A “guideline strongly recommend[s] ... methods, actions, practices, or processes to 

consider in absence of applicable standards [or] best practices that [are] not required.” 

As currently drafted, this Standard does not prescribe “uniform methods, actions, 

practices, or processes, protocols.” In addition, it does not address one crucial 

component that OSAC Standards should contain — advice on reporting and testifying. 

In theory, this component could be the subject of a separate Standard, but a more 

comprehensive Standard would be preferable, and there is no clear benefit to the 

community in placing an incomplete one, with no improvements whatsoever, on the 

registry.

Not Persuasive. This document is an ASTM Standard Guide. This document does not describe a 

prescriptive method, process or protocol. In agreement with the LRC comment, advice on 

reporting and testifying should be the subject of a separate document.

Therefore, detailed comments and suggestions for refining and expanding this 

draft follow. The first part lists concerns that should prompt significant revisions to 

achieve a document suitable for inclusion in the registry. The second part presents 

serious drafting issues that should be addressed if the subcommittee or the SAC 
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concludes that the matters in Part I (or problems identified by other reviewers) warrant 

revising ASTM E 2548−11 rather than adopting it without change.

1. Concerns about Content

Section 4.1 does not adequately explain why “specific sampling strategies are 

not defined in this guide.” (Also, the word “guide” may not be appropriate for a 

mandatory standard as defined in the QIC presentation.) If laws vary, specific strategies 

can be specified for at least a few, typical laws. Or, a rigorous strategy that would be 

acceptable everywhere can be presented as such — and made mandatory or 

designated a best practice (if it is indeed the best). Moreover, it is not obvious that the 

law in any U.S. jurisdiction precludes admitting probability sample data and 

extrapolations to population parameters. Some jurisdictions may require direct proof of 

total weight—no extrapolating—to establish beyond a reasonable doubt that total weight 

exceeds a given threshold when that quantity is an essential element of the crime. E.g., 

State v. Robinson, 517 N.W.2d 336 (Minn. 1994). What sampling method should be 

used in these jurisdictions?

Not persuasive. This is not a document intended to present a prescriptive sampling strategy. 

Sampling schemes will vary and are based on jurisdictional requirements and specific case 

circumstances. With so many different variations throughout the US, finding a consensus 

strategy applicable to all jurisdictions would be difficult and most likely impossible. Even 

accreditation bodies do not mandate a certain plan be followed but rather that a plan followed 

by a laboratory meets certain criteria. It is very important to leave some flexibility as 

designating a specific sampling methodology will not work in some jurisdictions.

Section 4.2.2 states that “Statistically selected units shall be analyzed to meet 

Practice E2329 if statistical inferences are to be made about the whole population.” 

E2329 governs the identification of material. Why would there be one set of 

requirements on how to identify material when an inference to a larger population is 

necessary and a different set of requirements when the analysis of a single unit is 

sufficient to prove what is necessary (e.g., “Are there any proscribed substances 

present?”)? Furthermore, incorporating E2329 presumes that it is suitable for inclusion 

in the OSAC registry. The adequacy of E2329 needs to be established first. This issue 

recurs later in the proposed Standard. If a Standard is not self-contained, all its parts 
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must be considered at once. This would entail providing the public with access to all the 

relevant ASTM documents.

Not persuasive. Section 4.2.2 quoted above has been misinterpreted by the LRC. Sampling and 

analysis are separate procedures in the forensic laboratory. Section 4.2.2 applies to multi-unit 

exhibit populations where not all units will be tested, but where the analysis conclusions will be 

stated in the form of a population inference. Section 4.2.2 simply states that the selected units 

should be analyzed as per E2329, in much the same way as a single-unit exhibit must also be 

analyzed as per E2329. The language quoted does not establish different identification 

requirements for the two different scenarios.

Reference to E2329 is unavoidable and the fact that it is not in the OSAC Registry yet is an 

unavoidable aspect of the process of implementing existing forensic standards in the OSAC 

Registry. E2329 is currently undergoing OSAC evaluation as well, but that should not be an 

impediment to the evaluation and inclusion of E2548.

The terminology within Figure 1 is confusing. It is sufficiently problematic that it 

rises to the level of a substantive rather than merely a stylistic concern. It seems like the 

middle level in the diagram is about the determination of sample size rather than a full 

“sampling plan.” Thus, the terms “sampling procedure” and “sampling plan” should be 

defined. Doing so might answer questions (a)–(d) below. Clearer terminology comes 

from David Freedman, who wrote that “Methods for choosing samples are called 

‘designs.’ Good designs involve the use of probability methods, minimizing subjective 

judgment in the choice of units to survey. Samples drawn using probability methods are 

called ‘probability samples.’” David A. Freedman, Sampling, available on the 

Department of Statistics, University of California (Berkeley) website.

Not persuasive. The middle level of Figure 1 is not about determination of sample size. It 

establishes the foundation of a plan, as sampling plans can be statistical or not. The actual 

sample size is determined based on laboratory requirements and jurisdiction. For example, one 

laboratory may only need to provide evidence that a controlled substance is present in at least 

50% of the seizure population while a separate laboratory’s jurisdiction may require proof of at 

least 90% of the population containing the drug. The required sample size would be different for 

these two laboratories.
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a. Are there “hypergeometric sampling plans”? A sampling plan should specify 

the sample size (or a procedure for stopping the sampling if results on the 

sampled items up to that point make further testing unnecessary). For 

sampling a finite population without replacement, the hypergeometric 

probability distribution applies to sample-size computations. But how does 

that make the sampling plan hypergeometric? The simplest “plan,” one would 

think, is to take a random sample of a size determined in light of the samplesize as computed with the hypergeometric distribution. The result is just a 

simple random sample.

Not persuasive. The quoted text “hypergeometric sampling plans” is not found in the document. 

Sampling plans based on the discrete hypergeometric sampling distribution are extensively 

reported in the statistical and forensic literature.

b. The fundamental distinction among the “statistical plans” on the far right of the 

figure is the divide between frequentist and Bayesian computations for 

sample size. Is not the frequentist approach always to use the 

hypergeometric distribution or a good approximation to it? 

Agree. Most frequentist sampling procedures currently used throughout seized drugs 

laboratories are based on the hypergeometric distribution. The intent of the figure is not to limit 

the list to just one approach, but also to inform the user of the document as to other approaches 

available. 

c. Suppose there is a “judicial requirement” to use a fixed percentage of the 

finite population as a sample size. (It might also be statutory or 

administrative.) Why isn’t this statistical method of fixing the sample size a 

“statistical plan”? It is not a good idea, but it is part of a plan that uses a 

statistic.

Not persuasive. The essence of a statistical sampling plan is that a probability-based approach 

must be used for sample selection. This implies the use of random sampling. A laboratory may 

choose to sample a fixed number of items. However, the statistical inference on the population is 
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only appropriate if random sampling has occurred. Simply stating a sample size (a number) 

does not make a selection or plan statistical.

d. Is the √N “plan” the old √N + 1 rule of thumb for determining sample size? 

Why should it ever be used as part of a sampling plan? See J. Muralimanohar 

& K. Jaianan, Determination of Effectiveness of the ‘Square Root of N Plus 

One’ Rule in Lot Acceptance Sampling Using an Operating Characteristic 

Curve, Quality Assurance Journal, 14(1-2): 33–37, 2011. This sample size is 

not based on a probability calculation, but why does that make it and the 

subsequent sampling “non-statistical”? If probability sampling has been 

conducted, statistical inferences and estimates have the same meaning 

regardless of how the fixed sample size was determined.

See previous response. The listed sample selection rules (√N and √N + 1) are often used by 

laboratories in situations where a probability-based inference on the population is not needed. 

Random sampling is not required in these situations, making these procedures non-statistical. 

This is very typical for laboratories doing analysis under specific jurisdictional weight-threshold 

penalties.

Section 5.5.1 speaks of “The probability that a given percentage of the population 

contains the drug of interest or is positive for a given characteristic.” The Standard 

should make it clear that this posterior probability of a population parameter cannot be 

computed with any of the frequentist methods mentioned in the Standard.

Not persuasive. This comment appears to originate from a misinterpretation of the statistical 

language employed. The quoted text is the standard sampling hypothesis tested via frequentist 

sampling methods based on the hypergeometric probability distribution.

The Guidelines on Representative Drug Sampling noted in Section 5.5.1.2(2) 

contains errors corrected in the later version adopted by UNOCD in 2009. The newer 

document could be cited in Section 5.6.2.2 as well, since it discusses so-called “black 

box” methods (which are one way to draw a probability sample) more clearly than this 

Standard does.
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Editorial.

Section 5.5.2.2 seems to say that whenever management directs it, scientific 

sampling can be abandoned. That is not what is intended, and the Standard should 

offer more guidance on when to depart from scientific methods.

Not persuasive. Section 5.5.2.2 states “Selection of a single unit from a multiple unit population 

may be appropriate under certain circumstances (for example, management directives and 

legislative or judicial requirements, or both).” There is no language suggesting users to 

“abandon scientific sampling.” Section 5.5.2.2 is meant to address cases where it may be 

enough for a laboratory to simply analyze one unit. This may be due to legal, safety, and other 

reasons. In this case, no inference need be made as to the contents of the population.

Section 5.6.2 does not actually define the commonly misunderstood term 

“random sample,” and this may not be the best term to use. Sometimes, “random 

sample” denotes a sample drawn by simple random sampling (SRS), but SRS is just the 

simplest form of probability sampling. The key distinction is between probability 

sampling, however it is achieved, and convenience sampling. Is the section intended to 

recommend (or require) probability sampling unless impractical? That would be good, 

and the section also ought to give guidance — at least an example — on when 

probability sampling is not practical.

Not persuasive. The intent of section 5.6.2 is to describe the selection of a random sample, not to 

define it. For clarification, simple random sampling (SRS) is only one type of sampling, as are 

systematic and stratified random sampling. On the other hand, convenience (aka opportunity) 

sampling is only one type of arbitrary sampling. Others examples include judgement, quota and 

snowball sampling. The intent of this section is not to recommend (or require) probability 

sampling. Whether a laboratory chooses to implement a sampling plan with the possibility for 

population inference is their choice, based on accreditation and jurisdictional requirements.

Section 7.1 states that “Inferences based on use of a sampling plan and 

concomitant analysis shall be documented.” I am not sure what “concomitant analysis” 

means, since the analysis of the units normally will come after the sample is drawn.
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Not persuasive. The adjective is fitting as written.

The section on reporting needs more body. How should the results of the 

analyses be presented in a report and in court? Should not the full sampling plan be 

stated — the mechanism for drawing samples (e.g., blinded, which is to say, “black box” 

sampling, or selecting from numbered samples by a table of random numbers); the 

sample size, and the kind of sampling (SRS, stratified, etc.)? It is not enough merely to 

state that “the results are based on a sampling plan,” as Section 8.1.1 seems to 

contemplate.

Editorial. The subject of reporting will be addressed in a future Seized Drug subcommittee 

document.

 

The results themselves always should be stated as in the example in Section 

8.1.2 — “2 of 100 bags were analyzed and found to contain Cocaine.” When probability 

sampling has been employed, more can be said. But what would this be? A confidence 

interval? With what confidence coefficient? With what definition of “confidence”? A 

frequentist test of a hypothesis? Explained how? A Bayesian conclusion such as “There 

is a probability of 90% that the weight of the cocaine in the shipment seized exceeds X” 

(if the analysis is Bayesian and the prior distribution and the basis for it are presented)? 

To be of the most benefit to analysts, lawyers, and courts, the Standard should do more 

to spell out the “[s]ampling information [that] shall be included in reports.” 

Editorial. The subject of reporting will be addressed in a future Seized Drug subcommittee 

document. The quote text should not be interpreted as an exclusively Bayesian conclusion, as it 

is also the routine hypothesis tested using a hypergeometric probability based sampling 

procedure.

2. Drafting Problems

Section 1.2 states that “This guide cannot replace knowledge, skill, or ability 

acquired through appropriate education, training, and experience and should be used in 

conjunction with sound professional judgment.” Either this goes without saying or it is 

dangerously broad. It might be misconstrued to mean that someone ostensibly 
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conducting probability sampling, for example, can depart from the sampling plan so as 

to exercise a putative skill to pick the sample units based on experience and 

professional judgment. That would vitiate the protection probability sampling offers 

against bias and the value of probability sampling in enabling an estimate of precision.

Not persuasive. This is standard language in ASTM documents. It is intended to avoid use of 

this document by someone that does not have the appropriate education, training, etc.

Section 3.3 states that “By developing a sampling strategy and implementing 

appropriate sampling schemes, as illustrated in Fig. 1, a laboratory will minimize the 

total number of required analytical determinations, while ensuring that all relevant legal 

and scientific requirements are met.” I think this is intended to say that “By developing 

and implementing a suitable sampling strategy, as illustrated in Fig. 1, a laboratory can 

reduce the number of analytical determinations required to meet legal and scientific 

requirements for producing reliable and unbiased evidence of the relevant features of a 

population.”

Not persuasive. There isn’t a discernable difference in how each of these is phrased.

Why does section 4.2 merely “recommend” that the “key points be addressed”? If 

these points are key, they must be addressed.

Editorial. Will be address via SDO review.

Section 4.2.1 states that “Sampling may be statistical or non-statistical.” Would it 

be clearer to state that “Whether probability sampling is essential depends on the 

quantity to be estimated or determined and the nature of the population from which a 

sample is drawn”? The terms “statistical sampling” and “non-statistical sampling” ought 

to be defined. Indeed, there is a good argument that they should be abandoned, and 

that “probability sampling” and “convenience sampling” should replace them.

Editorial. The suggested alternate language will be evaluated through SDO review.
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Not persuasive. Convenience sampling is only one type of non-statistical sampling, so its use 

would be incorrect.

Section 4.2.1.2 states that for inferring population characteristics from a sample, 

“the plan shall be statistically based and limits of the inference documented.” The 

intended meaning could be clarified. Is systematic sampling “statistically based”? Or is 

“statistically based sampling” limited to probability sampling? What does “limits of the 

inference” mean? An interval estimate? Conditional error probabilities for a hypothesis 

test?

Not persuasive. Systematic sampling is a variation of simple random sampling (SRS), and 

therefore, allows for a population inference if employed. The general intent of this section is that 

only if samples are taken randomly and appropriately may an inference be made to a population, 

and the limits of the inference must be documented. The limits of the inference include clearly 

stating what was analyzed, the inferences drawn from such testing and the associated 

measurement uncertainty. Measurement uncertainty is generally expressed as an expanded 

uncertainty and includes the coverage probability (i.e. percent level of confidence).

For Section 5.2 and the sections under the heading “SAMPLING PLAN,” is 

“population” defined in the Standard? What is an “exhibit”? What is a “unit”? The OECD 

and the International Statistical Institute define “unit” as follows: “A sampling unit is one 

of the units into which an aggregate is divided for the purpose of sampling, each unit 

being regarded as individual and indivisible when the selection is made.” 

https://stats.oecd.org/glossary/detail.asp?ID=2381. If the population consists of a single 

unit, why speak of sampling? 

In Section 5.4, what is a “bulk population”?

Not persuasive. These are commonly used terms in forensic and testing laboratories.

David Kaye

Legal Resource Committee

The following members of the LRC agree with comments made by David Kaye:

Barry Scheck, Jennifer Friedman, David Moran and Ron Reinstein.
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___________________________________________________

Comment by LRC Member Jennifer Friedman:

Comments from Jennifer Friedman on Proposed Standard E2548 Standard Guide for 

Sampling Seized Drugs for Qualitative and Quantitative Analysis:

I do not believe this standard is ready to be published in the OSAC registry. My 

reasons for this opinion are set forth below.

1.2 This is a proposed standard therefore it should be described as a standard 

not a practice. Additionally, this seems to suggest that it would be appropriate not be 

follow the standard if the analysts “experience, education, or training” dictated it should 

not be followed. 

Not persuasive. This is an ASTM Standard Guide, not a Practice as quote above; and these 

classifications are based on ASTM procedures.

The partial quote is extracted from standard language in ASTM documents. It is intended to 

avoid use of this document by someone that does not have the appropriate education, training, 

etc.

4.2.1 states sampling may be statistical or non-statistical. Both terms need to be 

clearly defined. The definition offered for statistical “probability-based” does not 

sufficiently define the term and there is no definition offered for non-statistical. In section 

5.5.1.1 examples of statistical methods are listed. 5.5.2.1 gives examples of nonstatistical methods. If this document is standard, there should be a list of which methods 

have been validated and thus may be employed. It should not be left to the examiner to 

decide.

Not persuasive. The terms statistical is defined in Note 1 within section 4.2.1. It is to be 

interpreted that all other situations are otherwise non-statistical.

Not persuasive. These are not testing methods. Sampling methods are based on established 

statistical and probability principles that allow for conclusions with a reasonable level of 

confidence.
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4.2.2 includes by reference E2329. This may present a problem if E2329 is not 

incorporated into the OSAC registry,

Previously considered and discussed above.

5.6.2.2 states “random sampling of items using random table may not be 

practical in all cases. In these instances, an alternate sampling plan shall be designed 

and documented to approach random selection.” This section should detail under what 

circumstances random sampling is not appropriate and set forth what method should be 

used when this occurs.

Not persuasive. This is a general document. Evidence heterogeneity from case to case and 

throughout jurisdictions makes it unrealistic to list all circumstances where either random or 

nonrandom sampling should be employed.

6.1 and 6.2 again reference E2329 which could be problematic for the reason 

described above.

Previously considered.

7 & 8 need to clearly set out how the results should be reported, what 

conclusions the analyst may make if random sampling is employed, what the limits of 

the opinion are so that the fact-finder may be able to appropriately assess the weight of 

the opinion.

Previously considered.

Jennifer Friedman

Legal Resource Committee

The following members of the LRC agree with comment made by Jennifer 

Friedman:

Barry Scheck, David Kaye

_______________________________________________

Comment by LRC Member Christopher Plourd:
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A probability based sampling approach for the forensic analysis of multiple 

containers of seized drugs is being proposed by the Seized Drugs subcommittee of the 

Chemistry-Instrumental Scientific Area Committee (“SAC”) as an Organization of 

Forensic Scientific Area Committee (hereinafter “OSAC”) approved standard.

This standard is identified and described as “E2548-11 Standard Guide for Sampling 

Seized Drugs for Qualitative and Quantitative Analysis”. A statistical-based chemical

analytical sampling approach for seized drugs in containers should be designed to 

answer questions of both content weight and illicit drug identity. The standard describes 

a sampling method that has been used and is well understood in the forensic scientific 

community. (See: Sampling of Street Drug Exhibits, Journal of Forensic Sciences,

1993, 38(3): 641-648; How many samples from a drug seizure need to be analyzed?

Journal of Forensic Sciences [2001, 46(6):1456-1461; Bayesian Adaptive approach to 

estimating Sample Sizes for Seizures of Illicit Drugs; Journal of Forensic Sciences

[2012, 57(1):80-85]

From a legal perspective one critical question asked is: does existing scientific 

research support the E2548-11 standard? It appears that E2548-11 on the basis of the 

information in the Standard, the literature cited and my independent research, the 

technique demonstrates general-acceptance within the relevant scientific community. 

The subject of the standard, having been in use without any scientific controversy for 

over three decades, is not a new or novel technique nor is it a novel application of an 

older technique or method. Therefore the E2548-11 standard would not likely be the 

subject of a Frye challenge. [Frye v. United States, 293 F. 1013 (D.C. App. 1923)] The 

directives of the standard, for the most part, are specific and clear as to what they 

require and or recommend.

The underlying scientific probability statements, in my opinion, are valid. The 

E2548-11 standard references sampling strategies and notes that the sampling 

procedures are divided into statistical and non-statistical. Statistical procedures

(presumably hypergeometric, Bayesian, and other probability-based approaches) are to 

be developed by the individual laboratory. If a population opinion is given from samples 

tested, then the plan shall be statistically based and documented. (“4.2.1.2 If an 

inference about the whole population is to be drawn from a sample, then the plan shall 
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be statistically based and limits of the inference shall be documented.”) Expert 

testimony based on the use of this standard therefore would be based on matter that is 

of a type that reasonably may be relied upon by an expert in forming an opinion upon 

the subject to which his testimony relates.

Error rates associated with the techniques are not a concern if the E2549 

standard is applied as recommended. Uncertainty associated with measurements 

obtained by using the standard techniques as prescribed are described and have been 

the subject of publications in the scientific literature.( “4.2.2 Statistically selected units 

shall be analyzed to meet Practice E2329 if statistical inferences are to be made about 

the whole population.”)

The techniques used by a forensic chemist using the E2548-11 standard would 

in my opinion not be impermissibly subjective or speculative. Any proffered testimony by 

an qualified expert from a laboratory that adopts and uses the E2548-11 standard who 

testifies as an expert witness, should be admissible under the authority of Daubert v. 

Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S.Ct. 1786, 125 L.Ed.2d 469

(1993). The rigorous Daubert admissibility rule imposes a special gatekeeping 

obligation on the trial court to ensure the reliability of all expert testimony. Specifically, 

several procedural and substantive limitations upon the admission of expert scientific 

testimony are in place with Daubert to ensure that unreliable expertise would be 

excluded from the jury's consideration. Daubert v. Merrell Dow Pharmaceuticals, Inc., 

509 U.S. 579 (1993) and Kumho Tire Co., LTD., v. Carmichael, 526 U.S. 137 (1999). 

Either under Frye or Daubert, reliable evidence should be heard by the Trier of fact 

under a weight of the evidence evaluation. The key question of admissibility of expert 

testimony under Frye/Daubert is reliability and relevance. If the methods are reliable, 

the theory is typically “generally accepted” in the scientific community. Use of the 

E2548-11 standard seems to meet the reliability test.

Of legal use and importance the E2548-11 standard address’s due process-disclosure

concerns because the standard requires documentation of all underlying data and 

assumptions.

There are no adverse appellate court rulings on the admissibility of the 

techniques described in the E2548-11 standard. Use of the E2548-11 as an OSAC 
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approved standard would be expected to meet or exceed any legal admissibility 

requirements in jurisdictions within the United States.

Subject to an evaluation of the concerns raised by David Kaye and Ted Hunt I 

would recommend that the Chemistry-Instrumental Scientific Area Committee (“SAC”) 

Approve the E2548-11standard as an Organization of Forensic Scientific Area 

Committee (hereinafter “OSAC”) approved standard.

Christopher J. Plourd

Legal Resource Committee

The following LRC members agree with comments made by Christopher Plourd:

Ron Reinstein, Lynn Garcia and Ray Miller.

Comments made by LRC member Barry Scheck:

I am in agreement with all of David Kaye's comments as well as the comments of 

Jennifer Friedman. I am grateful to my colleagues for their comprehensive analysis.

I would like to emphasize concerns expressed in these comments that the deficiencies 

in the statistical explanations offered in all of these standards is troubling and not ready 

for court, whether one is in a Frye or Daubert jurisdiction. These should be rejected from 

the OSAC Registry and, hopefully, the OSAC subcommittee and/or ASTM will revise the 

proposed standards to follow the template laid out in the Technical Merit Worksheets. In 

that connection, I cannot imagine that the requirement of general acceptance in the 

scientific community, particularly among statisticians, can be met, nor the requirements 

of clearly identifying limitations and weaknesses in the methodology or an explanation 

of how it is "fit for purpose."

Not persuasive. Not sure what is referred to as “deficiencies in the statistical explanations 

offered”. There are no statistical explanations offered in this document. The general sampling 

guidelines discussed in this document are statistically based, when applicable, and have been 

used and nationally and internationally accepted by seized drug laboratories and courts for 

many years. Their fitness for purpose has therefore been demonstrated.

It is unrealistic to expect previously vetted and published ASTM documents to fulfill the 

requirements just recently established by OSAC, as they are completely separate institutions.
LRC Comments to ASTM E2548-11

Page 17 of 21

This comment does not offer any specific explanation as to how this document does not meet “the 

requirement of general acceptance in the scientific community, particularly among 

statisticians”. It appears the document has been misinterpreted as describing a particular 

methodology.

Barry Scheck

Legal Resource Committee

Comments made by LRC member Ted Hunt:

GENERAL COMMENTS

David Kaye correctly observed that the July 27, 2015, QIC presentation stated 

that documentary standards and guidelines must demonstrate "technical merit," which 

includes "detailed scope," "fitness for purpose," "uncertainty measurement and potential 

bias," and "method validation, as appropriate" in order to be included on the OSAC 

Registry.

The same presentation also stated that a standard, "specifies uniform methods, 

actions, practices, or processes, protocols," and that "compliance [is] recommended to 

be mandatory and modified only under unusual circumstances."

There is no question that this document fails to meet those requirements. This, 

however, is less a reflection on the substantive merit of E2548 - 11 (given its real 

purpose) than the present failure of the OSAC to strike a clear distinction between 

"standardized methods" and "consensus documentary standards" for purposes of the 

technical merit requirements set forth for OSAC standards and guidelines. 

The only verbiage that seemed to separate these two distinct types of 

"standards" in the presentation was the inclusion of the words, "as appropriate." This 

cryptic reference is insufficient guidance with which to de-conflate which type of 

standard (high-level consensus practice standard vs. standardized method) is under 

consideration, and gives no guidance at all about the OSAC-required components of 

this second type of standard — a high-level consensus practice standard — that sets 

forth minimum requirements for labs to incorporate within their internally validated 

analytical procedures for a given technology and/or method.
LRC Comments to ASTM E2548-11

Page 18 of 21

There is no question that E2548 - 11 is not a "standardized method." Its scope is 

not detailed, its "purpose" merely states that it covers "minimum considerations" for 

"sampling of seized drugs for qualitative and quantitative analysis"; uncertainty of 

measurement is not specifically addressed; sampling bias is only addressed with the 

single statement, "A random sample is one selected without bias"; and method 

validation is not addressed at all — but that is simply because E2548 - 11 is not a 

"method."

Rather, E2548 - 11 appears to be a "consensus documentary standard" which —

as other documentary standards do — addresses not how a particular laboratory’s 

sampling method shall be performed, but rather that each laboratory engaged in 

sampling shall follow the "minimum considerations" set forth for sampling "seized drugs 

for qualitative and quantitative analysis."

Unfortunately, however, there is currently no OSAC guidance (that I know of) on 

the minimum requirements for this type of "standard" (consensus documentary 

standard) — other than the "as appropriate" language noted above.

Given the present absence of a distinction between "consensus documentary 

standards" and "standardized methods" in the OSAC nomenclature, this "standard" fails 

a test it was never originally designed to take. 

The OSAC should remedy this omission by specifically recognizing the distinction 

between these two distinct types of "standards" and setting forth separate criteria by 

which high-level consensus documents — such as this one — are to be judged.

///

///

SPECIFIC COMMENTS

My comments above notwithstanding, E2548 - 11 can be improved upon as a 

"consensus documentary standard." 

1. Given its proposed placement in the OSAC Registry, I think the title, 

"Standard Guide for Sampling ...." is confusing. The title hedges by using 

both the terms "standard" and "guide." Further, the document, in places, 

reads like a “guideline” rather than a “standard” by using the term 
LRC Comments to ASTM E2548-11

Page 19 of 21

"recommended" (4.2), (5.6.1.2), (6.1); "should" (5.6.2.1); and "may" (4.2.1.1), 

(5.4.2), (5.5), (5.5.2.2).

Not persuasive. This is the ASTM verbiage.

In other places, the document reads like a standard by using the term "shall" 

(4.2.1.2), (4.2.2), (5.2.3), (5.4), (5.6.2.2), (6.2), (7.1), (8.1); and "must" (8.1.1) (8.1.2).

The combination of this directive and permissive verbiage in the document 

should be re-examined if E2548-11 will go forward as a "standard."

2. 5.6.2.1 states that "For statistical approaches it is recommended that 

random sampling be conducted." If a statistical approach is probabilistic in 

nature, and is meant to support inferences drawn regarding an entire 

population, I don't see how sampling could validly be conducted by anything 

other than an appropriately chosen and appropriately random method — so 

I'm a bit confused by the permissive word, "recommended."

Editorial. The Seized Drugs subcommittee will request revision of the language through the 

SDO process. For clarification, the quoted text is found in section 5.6.1.2, not 5.6.2.1 as noted 

above. 

3. 7.1 states, "Inferences based on the use of a sampling plan and concomitant 

analysis should be documented." The use of the term "concomitant" here is 

confusing because sampling and analysis will not literally be conducted in a 

"concomitant" manner — and if they were that would present its own set of 

problems. The word "subsequent" instead of "concomitant" seems more 

appropriate here.

Not persuasive. Concomitant means “associated, parallel, related, etc.”, which is the intended 

meaning here. The analysis is subsequent to each sampling selection, but not necessarily the 

complete sampling action. Concomitant is a more general term and is appropriate for this 

purpose.
LRC Comments to ASTM E2548-11

Page 20 of 21

Also, consider adding the requirement that "key assumptions" which are 

incorporated into the sampling plan constructed by the lab should be documented as 

well.

4. Consider redrafting 5.5.2.2 to make it clear (consistent with David Kaye's 

recommendation) that this language does not mean that the otherwise 

scientifically valid and reliable selection of a single unit from a multiple unit 

population should yield to management directives, legislative, or judicial 

requirements.

Previously considered. This section merely states that a laboratory may choose to sample as few 

as one unit from a population, but that choice comes with limits to making an inference to the 

population.

5. Where key "terms of art" are used within this document and are currently 

defined in another existing standard, then consider some direct reference to that 

standard (where those terms are defined) within the present document when the terms 

of art are used. If those terms are not defined within an existing standard, they should 

be added to the OSAC list of definitions before the standard is included on the OSAC 

Registry.

6. Perhaps 1.2 could be rephrased to state that this standard should be used in 

conjunction with the analyst's knowledge, skill, or ability acquired through appropriate 

education, training, and experience and sound professional judgment — rather than that 

it cannot "replace" those attributes. The guidance set forth in this document — as with 

all scientific standards and procedures — will always necessarily be executed 

concurrently with the judgment and discretion of a trained and experienced analyst. 

Neither the expert nor the method can exist or function without the other when 

producing scientifically sound and reliable results.

Previously considered.

Ted Hunt

Legal Resource Committee
LRC Comments to ASTM E2548-11

Page 21 of 21

The following LRC members agree with comments made by Ted Hunt:

David Kaye and Ron Reinstein.

___________________________________________________

DISCLAIMER: The failure of any member of the Legal Resource committee (LRC) 

to provide a comment, identify a legal issue or join in another LRC comment 

should not be interpreted as a disagreement or endorsement of the comment, the 

standard or its legal sufficiency.