No Flowering Tops, No Drug: The Latest Spanish Supreme Court Interpretation of Cannabis Under International Law

Supreme Court of Spain, Madrid

"Seeds and leaves not attached to the flowering tops are not subject to control as cannabis." — STS 47/2026

I. The Judgment: Facts, Procedural History and Ruling

On 28 January 2026, the Second Chamber (Criminal Division) of the Spanish Supreme Court handed down Judgment No. 47/2026 (ECLI:ES:TS:2026:248), with Justice Ana María Ferrer García as rapporteur. The ruling dismisses an appeal in cassation brought by the Public Prosecutor and upholds the acquittal of the accused — identified in the proceedings as Conrado — of the drug trafficking offence under Article 368 of the Spanish Criminal Code (Código Penal, CP).

The proven facts are as follows: on 11 February 2021, at approximately 12:20, police found in the accused’s home in Gójar (Granada) 832 cannabis plant cuttings, duly analysed as cannabis leaves with a THC content of 2.0% and a net weight of 2,496 grams, together with 156 cannabis plants, similarly analysed as cannabis leaves with a THC content of 2.2% and a net weight of 748 grams. The accused had also made an unauthorised connection to the electricity network, tampering with cables and the meter, causing the distribution company a financial loss of €413.98.

The Granada Criminal Court No. 6 (judgment of 16 May 2022) acquitted the accused of the drug offence and convicted him solely of electricity fraud. The Granada Provincial Court (Section 1, judgment of 22 December 2022) upheld that decision in full. The Public Prosecutor appealed in cassation, invoking Article 849(1) of the Criminal Procedure Act (LECrim) and alleging improper non-application of Article 368 CP.

The Supreme Court dismisses the appeal. The final conviction is limited to electricity fraud: a fine of four months at a daily rate of €7, with one day’s deprivation of liberty for every two unpaid instalments, and compensation of €413.98 to the distribution company.

II. The Legal Crux: What is Cannabis under International Law?

A. The 1961 Single Convention on Narcotic Drugs: a binding definition

The key to the judgment lies in the correct interpretation of the normative element of Article 368 CP — ‘toxic drugs, narcotic drugs or psychotropic substances’ — by reference to the international treaties ratified by Spain. The central instrument is the Single Convention on Narcotic Drugs of 1961, as amended by the 1972 Protocol.

Article 1(1)(b) of the Single Convention defines ‘cannabis’ as follows:

“Cannabis means the flowering or fruiting tops of the cannabis plant (excluding the seeds and leaves when not accompanied by the tops) from which the resin has not been extracted, by whatever name they may be designated.”

The Convention includes in its Schedule I ‘cannabis and cannabis resin and extracts and tinctures of cannabis’, and in Schedule IV ‘cannabis and cannabis resin’, but not the plant in its entirety. The consequence is unambiguous: leaves not accompanied by the tops, and seeds, are expressly excluded from international control.

B. The consolidated line of case law: STS 205/2020, STS 855/2021 and STS 288/2023

STS 47/2026 does not stand alone. It is the apex of a jurisprudential line that the Supreme Court itself systematises with precision:

STS 205/2020 (20 May 2020) established the foundational principle: the status of a narcotic drug for the purposes of Article 368 CP “is not coextensive with the whole plant”, since the Single Convention expressly excludes seeds and leaves not accompanied by the tops.

STS 855/2021 (10 November 2021) applied this principle even in a case with a high THC content (9.6% and 8.2%), setting aside the aggravated ‘substantial quantity’ finding because, once the non-controlled parts were deducted, it could not be excluded that the seized substance fell below the ten-kilogram threshold for the aggravated offence.

STS 288/2023 (25 April 2023) updated the doctrine in light of Directive 2017/2103/EU of the European Parliament and of the Council of 15 November 2017, and the December 2020 decision of the UN Commission on Narcotic Drugs to remove cannabis from Schedule IV while retaining it in Schedule I. It confirmed that “cannabis is not controlled based on its THC content but insofar as it consists of flowering tops together with the leaves attached to them, and resin”.

STS 47/2026 crowns this progression and elevates the criterion to unified cassation doctrine, binding on all Spanish criminal courts.

III. The Supreme Court’s Reasoning in STS 47/2026

A. The cultivation charge is dismissed

The Prosecutor argued that the facts should be subsumed under the cultivation variant of Article 368 CP, submitting that the plants, although not yet flowering, were not at a minimal stage of development and that the offence should be considered consummated — not attempted — at an advanced cultivation stage, in line with STS 306/2022.

The Supreme Court rejects this argument. The statement of proven facts — immutable in cassation for errors of law — does not declare a cultivation activity: the trial court “excluded the assertion heading the public prosecutor’s factual account: ‘the accused was carrying out cultivation activities at the address...’”. Without that factual foundation, the conduct cannot be subsumed under the cultivation variant.

B. Possession requires the substance to be a drug

Having set aside cultivation, the only available basis for criminal liability was possession with intent to distribute. But that variant requires, as an indispensable preliminary, that the seized substance qualifies as a toxic or narcotic drug. And it is here that the Single Convention operates:

In accordance with [the international conventions], seeds and leaves not attached to the flowering tops of the cannabis plant are excluded from that status.” (STS 47/2026, Legal Ground 2, para. 3)

The 832 cuttings and 156 plants had been analysed as ‘cannabis plant leaves’ — not as flowering tops. Without flowering tops, there is no controlled cannabis. Without controlled cannabis, there is no subject matter for the offence under Article 368 CP.

C. High THC content does not alter the conclusion

The Prosecutor argued that the 2.0%–2.2% THC detected in the cuttings and plants demonstrated that these were cannabis sativa varieties apt for producing narcotics, and that any part of the plant exceeding 0.12%–0.3% THC should be treated as controlled.

The Supreme Court expressly rejects this argument. The Single Convention does not control cannabis based on THC content but based on the part of the plant in question. The reasoning is impeccable from the standpoint of the principle of legality:

To extend, without a normative instrument so providing, the concept of what must be considered a toxic drug or narcotic for criminal purposes sits ill with the principle of legality and legal certainty.” (STS 47/2026, Legal Ground 2, para. 3)

D. Article 28 of the Single Convention does not criminalise

The Court draws a conceptually vital distinction: the fact that Article 28 of the Single Convention requires States Parties to ‘take such measures as may be necessary to prevent the misuse of, and illicit traffic in, the leaves of the cannabis plant’ does not mean that this obligation must be discharged through criminal law:

Illegality is not identified exclusively with the criminal but also with the administrative, and the corresponding sanction must be structured through that channel.” (STS 47/2026, Legal Ground 2, para. 4)

This distinction between criminal and administrative illegality is fundamental: the Convention mandates control and regulation, not the automatic penalisation of all conduct relating to non-controlled parts of the plant.

IV. European Perspective: EU Law and the European Convention on Human Rights

A. EU Framework Decision 2004/757/JHA and Directive 2017/2103/EU

Council Framework Decision 2004/757/JHA of 25 October 2004 on illicit drug trafficking defines ‘drug’ by express reference to the 1961 Single Convention and the 1971 Vienna Convention. Directive 2017/2103/EU of 15 November 2017, which amended the Framework Decision, maintains this reference and adds that cannabis with a THC content above 0.3% causes harm to health and has the status of a narcotic drug.

The Spanish Supreme Court in STS 288/2023 — confirmed by STS 47/2026 — clarified that this directive does not modify the definition of ‘cannabis’ in Article 1(1)(b) of the Single Convention. The 0.3% THC threshold establishes a health-harm standard in relation to already-controlled parts of the plant — flowering tops and resin — but does not extend the scope of control to unflowered vegetative material.

Moreover, the CJEU judgment of 19 November 2020 in Case C-663/18 (Kanavape, concerning CBD oil) itself referred back to the definitions of the 1961 Single Convention in determining what constitutes a controlled substance, confirming that the international standard remains the decisive normative reference.

B. The principle of legality under the ECHR: Article 7

Seen through the lens of the European Convention on Human Rights, STS 47/2026 is a paradigmatic application of the nullum crimen sine lege principle enshrined in Article 7 ECHR. The European Court of Human Rights has consistently held that criminal rules must be accessible and foreseeable to the individual (Sunday Times v. United Kingdom, 1979; Kokkinakis v. Greece, 1993; Contrada v. Italy (No. 3), 2015).

To extend the concept of ‘narcotic drug’ under Article 368 CP to parts of the cannabis plant expressly excluded by the Single Convention — as the Public Prosecutor sought — would have amounted to an interpretation by analogy in malam partem incompatible with the foreseeability requirement of Article 7 ECHR. The Supreme Court states this with precision: extending the offence “sits ill with the principle of legality and legal certainty”.

Article 7 ECHR protects the individual against the retrospective or expansive application of criminal norms. When the normative element of the offence is integrated by reference to an international treaty — as Article 368 CP refers to the Single Convention — foreseeability must be measured against that treaty. If the treaty expressly excludes leaves not accompanied by flowering tops, the individual is entitled to rely on that exclusion as the outer boundary of the State’s punitive power.

V. Practical Implications for Defence Counsel

1. Forensic audit of the seized substance

The first practical consequence of STS 47/2026 is the need for a precise and disaggregated forensic analysis. The analytical report must expressly distinguish the proportion of the total seized material that corresponds to flowering or fruiting tops from the proportion corresponding to leaves not accompanied by tops, seeds, stems, and woody material. Defence counsel should request, from the outset of proceedings, that the official laboratory report does not merely record total weight and THC percentage, but morphologically identifies the part of the plant analysed.

2. Challenge to the subject matter of the offence

Where the seized substance consists entirely or substantially of leaves not attached to the flowering tops — including cuttings, vegetative-stage material, or unflowered plants — the defence must challenge the foundational premise of the charge: that the substance is a narcotic drug within the meaning of Article 368 CP and its international treaty counterparts. STS 47/2026 confirms that this argument is not marginal; it is consolidated cassation doctrine operative since 2020.

3. The high-THC argument as prosecutorial strategy

Prosecutors will seek, as was attempted in this case, to substitute the absence of flowering tops with evidence of high THC content. Defence counsel must counter this with the Supreme Court’s jurisprudence: the 0.3% THC threshold of Directive 2017/2103/EU does not redefine the subject matter of the offence; it merely establishes a health-harm threshold for already-controlled substances. Control depends on the part of the plant, not on the percentage of THC.

4. Distinguishing cultivation from possession of vegetative material

STS 47/2026 draws a precise distinction between the cultivation variant — which can reach consummation without flowering, once the crop is capable of serving the purpose for which it is grown (STS 306/2022) — and the mere possession of vegetative material. Where the statement of proven facts does not affirm a cultivation activity, the only available basis for liability is possession, which in turn requires the substance to be a drug. This double requirement — factual and normative — is the natural ground for the defence.

5. Article 7 ECHR as a route to the ECtHR

Where a national court converts into a conviction what the Supreme Court characterises as atypical conduct, the defence has Article 7 ECHR as a route to the European Court of Human Rights. The extension of the concept of ‘narcotic drug’ to parts of the plant expressly excluded by the Single Convention constitutes an interpretation by analogy in malam partem inconsistent with the foreseeability requirement. The ECtHR has quashed convictions based on unforeseeable judicial interpretations of the criminal offence (Contrada v. Italy (No. 3), 2015), and the same standard applies here.

6. Transnational perspective: harmonising the defence across Europe

STS 47/2026 is not an isolated Spanish development. The same Single Convention of 1961 governs all Member States of the Council of Europe and all Member States of the European Union. The definition of ‘cannabis’ in Article 1(1)(b) is identical under German, French, Italian, Belgian, Dutch, Swiss and Montenegrin law. In all these systems, the defence can and should invoke the principle that leaves not accompanied by flowering tops, and plants in the vegetative stage, do not constitute the controlled substance. Defence teams operating across multiple jurisdictions — as JDT members routinely do — have in STS 47/2026 a reference argument that can be deployed before any European criminal tribunal.

VI. Conclusion

International law defines cannabis. The Supreme Court applies it. The defence invokes it.

STS 47/2026 of 28 January 2026 is not merely an acquittal in a single case. It is the definitive consolidation of a doctrine rooted in international law, expressed in EU law, and directly reflective of the principle of legality guaranteed by Article 7 of the European Convention on Human Rights.

Its message is clear: the normative element of the drug trafficking offence — ‘narcotic drug’ — cannot be defined more broadly than the Single Convention of 1961 itself. Leaves not attached to the flowering tops and plants in the vegetative stage are not controlled cannabis. They are not drugs for criminal purposes. And without a subject matter, there is no offence.

For criminal defence lawyers in Spain and across Europe, this judgment is a first-order instrument. Not only in cannabis cases, but as an example of how binding international law, correctly invoked, can and must operate as a limit on the punitive power of the State. This is precisely the kind of argument that the Joint Defense Team — with defence lawyers across Germany, Italy, France, Spain, the Netherlands, Belgium, Switzerland and Montenegro — is built to develop and deploy.