Top of the Ninth – Guest blog: The Science Behind Lorenzo v. Whitaker and Lorenzo v. Sessions

Top of the Ninth – Guest blog: The Science Behind Lorenzo v. Whitaker and Lorenzo v. Sessions

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In order to better understand Lorenzo v. Whitaker, I asked our trusted guest blogger Sean Patrick McGinley a third-year law student at Boston College to explain the science behind the Ninth Circuit’s most recent decision. Thank goodness for the scientists who practice or will soon be practicing law (who don’t automatically go into intellectual property law). A huge thank you to Sean Patrick for explaining the science behind Lorenzo. Please enjoy!

Lorenzo v. Whitaker Explanation

On January 17, the Ninth Circuit issued a memorandum disposition essentially ending Lorenzo v. Sessions, 902 F.3d 930 (9th Cir. 2018). Lorenzo originally held that any conviction related to methamphetamine is overbroad because California’s definition of methamphetamine is broader than the federal definition. More specifically, California includes geometric and optical isomers of methamphetamine in its definition where the federal definition only includes optical isomers. In a previous post, I discussed the differences between the two types of isomers and why the definition matters. Although the Ninth Circuit agrees that the definition is overbroad, the Ninth Circuit withdrew the decision because, as the court explained, geometric isomers of methamphetamine do not exist. Lorenzo v. Whitaker, No. 15-70814, ___ Fed. App’x ___, 2019 WL 248978 (9th Cir. Jan. 17, 2019).

In my previous post, I said that although it does not seem like any geometric isomers are known, there is still a possibility that they exist. I, unfortunately, was unequivocally wrong. The Ninth Circuit is correct: methamphetamine does not, and cannot, have any geometric isomers.

The Science: Why a Geometric Isomer Cannot Exist

To explain why a geometric isomer cannot exist, I am going to start with the science. This explanation, in all honesty, does not impact the legal analysis. I just personally find it interesting. In order for a geometric isomer to exist, there must be a double-bond between two carbon atoms. For example, consider this graphic: 1

Both compounds have the same formula and general arrangement. But the chlorine (Cl) is “rotated” around the double-bond (C=C) on one side. This is a geometric isomer. Now, look at the model for methamphetamine: 2

Methamphetamine does not have the same carbon double-bond as the previous compound did. Because of this, it is chemically impossible for methamphetamine to have a geometric isomer. The Ninth Circuit is correct.

To note, the terms “geometric” and “optical” are incredibly outdated. They seem to harken back to the late 1980s and early 1990s, when the California and federal Controlled Substances Acts were enacted. Because of the age of the definitions, I tried researching whether the terms’ definitions have changed over time. I was hoping that the terms were used either more broadly or more loosely when either the California or federal Controlled Substances Act was enacted. After reading through multiple old chemistry textbooks and articles, it does not seem like the definition has changed over time.

Moving Forward: The Impact of Lorenzo v. Whitaker

First, it is important to note that the Ninth Circuit repealed Lorenzo v. Sessions because of the science and not the law. The now unpublished decision applies the same logic as the original opinion but recognizes the reality that a geometric isomer of methamphetamine does not exist. From this, it is reasonable to conclude that the Ninth Circuit could accept the same legal reasoning as posited in Lorenzo v. Sessions for other statutes.

And, more importantly, not all California statutes related to methamphetamine use the same, narrow definition. More specifically, both California Health & Safety Code §§ 11383.5(c) and 11383.7(c) use broader language. For example, in Section 11383.5(c), the statute is as follows:

“(c) Any person who possesses the optical, positional, or geometric isomer of any of the compounds listed in this section, with the intent to manufacture any of the following controlled substances, is guilty of a felony and shall be punished by imprisonment pursuant to subdivision (h) of Section 1170 of the Penal Code for two, four, or six years:

(1) Methamphetamine.

(2) Any analog of methamphetamine specified in subdivision (d) of Section 11055.

(3) N-ethylamphetamine.”

This statute, and Section 11383.7(c), includes optical, positional, and geometric isomers of methamphetamine. A positional isomer is a compound that has the same chemical makeup and skeleton, but the main atom groupings are in different locations. (Again, not particularly relevant for legal purposes, just personally interesting.) Methamphetamine undeniably has positional isomers. This includes dimethylphenethylamine, a flavoring agent commonly found in cereal, cheese, dairy products, fish, fruit, and meat.3 1-phenyl-3-aminobutane is also a positional isomer. Although I am not sure for what it is used, it is commercially available.4 If a non-citizen has a conviction under either of these two statutes, the reasoning in Lorenzo will likely apply in full force. Bottom line advise your clients who are arrested for methamphetamine or who are seeking post-conviction relief for methamphetamine convictions to suggest a plea to Cal. Health & Safety Code §§ 11383.5(c) and 11383.7(c) under the original logic in Lorenzo v. Sessions.

I have to give many thanks to my friend Coryna “Sam” Samon and her lab partners at Oregon State University. They were incredibly instrumental in me understanding the science behind isomers.


1 Jim Clark, Stereoisomerism – Geometric Isomerism, chemguide (Nov. 2012),

Methamphetamine, Wikipedia (last edited Jan. 16, 2019),

3 Mike Roberto, Eria Jarensis Extract/N-Phenethyl Dimethylamine: The Next Big Thing?, PricePlow (Aug. 1, 2017),

3-Amino-1-Phenylbutane, TCI America, Fisher Scientific (last visited Jan. 23, 2019),

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