Cannabis Cultivation Lawyers

Cannabis cultivation occupies a characteristic grey area of Spanish criminal law. Personal drug consumption is not a crime in Spain (only an administrative infraction under Organic Law 4/2015), but Art. 368 CP sanctions the cultivation, processing or trafficking of narcotic substances. There is no express regulation of self-cultivation for personal use, which has generated rich Supreme Court case-law that has consolidated criteria to differentiate unpunished self-cultivation from criminally typical cultivation. As criminal lawyers specialising in offences against public health, we articulate coordinated criminal, technical and expert defence focused on the self-consumption doctrine.

The typical modalities of criminally investigated cultivation are varied. Professional indoor cultivation at home with intensive electrical installation (400-1000W HPS or LED lamps, extractors, climate control, automated irrigation, frequently powered through illegal grid connection - Art. 255 CP). Outdoor cultivation on terraces, gardens and plots visible from outside, losing privacy coverage to invoke self-consumption. Cultivation in industrial warehouses or remote rural land, almost always classified as organised trafficking due to the scale of the operation. Cannabis social clubs, regulated by the Supreme Court's shared-consumption doctrine and subject to high criminal risk. And the production of extracts and derivatives (BHO, rosin, artisanal hashish) that multiply the concentration of active principle and the quantitative qualification.

The penalties applicable to cannabis trafficking (substance not causing serious harm to health, first paragraph of Art. 368 CP) are significantly more lenient than those for cocaine or heroin: prison from 1 to 3 years and fine. When the quantity exceeds the significant amount threshold (for marijuana, 10 kilograms by net weight; the 2.5 kg figure is the hashish threshold), the aggravated form of Art. 369.1.5 CP applies and imposes the next higher degree plus a fine of one to four times the value of the drug: prison from 3 years and 1 day to 4 years and 6 months. Where the cultivation is carried out from within a criminal organisation, Art. 369 bis CP raises the penalty to prison from 4 years and 6 months to 10 years for substances that do not cause serious harm to health, with the next higher degree for its leaders, managers or administrators. The instrumental offence of electricity defraudation (Art. 255 CP) adds fine of 3 to 12 months. Beyond the custodial penalty, full confiscation of the cultivation installation, vehicles used, cash and, where applicable, the property where the activity took place when criminal affectation is certified, proceeds.

The technical defence articulates several complementary lines. First, the counter-weighing expertise: the Guardia Civil habitually weighs the material in gross (entire plants including stems, roots, non-active leaves); we demand weighing exclusively of the dried flowering tops (buds with real THC concentration), a reduction that may reach 80-90% of gross weight and undo the qualification of significant amount. Second, the expert certification of habitual personal consumption of the grower through hair toxicology analysis, treatment-centre reports, medical history of therapeutic use and qualified testimony. Third, the nullity of the home search: mere cannabis smell or abnormal electrical consumption are not sufficient indications to violate Art. 18.2 SC; if the entry was made without sufficiently reasoned court order, all derived evidence is null. Fourth, the separation of offences between cultivation and electricity defraudation to avoid contagion effect in the penalty. Fifth, the challenge to evidence obtained through drones or thermal cameras on private property without specific judicial authorisation.

In current forensic practice we observe sustained growth in cannabis-cultivation proceedings, especially linked to professional indoor cultivations in rented flats, outdoor plantations in rural areas of the Levant, Galicia and Andalusia, cannabis social clubs investigated by the Narcotics Brigade, and the CBD and industrial hemp industry in the delicate regulatory balance between the AEMPS and the Public Prosecutor's Office. Act 17/1967 on narcotics, Organic Law 4/2015 on Citizen Security Protection, Organic Law 1/2025 on Justice Service Efficiency and recent case-law on circumstantial evidence, toxicological expertise and shared consumption have significantly hardened the evidentiary regime. At Alonso Sala, we tackle each file with forensic toxicology experts, electrical engineers, lawyers specialised in administrative-sanctioning law and tiered procedural strategy maximising the possibility of reconducting trafficking to unpunished self-consumption.

The police report almost always includes a weighing carried out on the spot and at the moment of the seizure, with the plant freshly cut and whole. That wet weight carries water, woody stems, roots and fan leaves: matter that will never reach the final product. Framing the charge on that figure means framing it on a datum that does not measure what the rule sets out to measure.

What we call for is a weighing of dried, stabilised substance, recorded in a document that separates the flowering tops from the rest of the plant material and expressly notes the deduction of stems and roots. On that basis a yield report is in order, translating the number of plants, their stage of development and the growing conditions into a reasoned estimate of usable product, with an explicit method and stated margins: a report that does not explain how it reaches its figure is not expert evidence, it is a number.

The distance between one magnitude and the other is not cosmetic. It decides whether the case crosses the significant amount threshold —and with it the jump of one degree in the sentence— and it also drives the fine, which Art. 377 CP requires to be calculated on the final price of the product. A valuation built on wet weight inflates both the financial penalty and the reach of the confiscation order.

One very common misunderstanding is worth clearing up. Art. 369.1 CP does not order the sentence to be imposed in its upper half: it imposes the penalties one degree higher than those of the preceding article plus a fine of one to four times the value of the drug. Applied to cannabis under Art. 70.1.1 CP, the range of one to three years becomes one of three years and one day to four years and six months.

The threshold, by contrast, does not appear in the Criminal Code. It was set by the Agreement of the Non-Jurisdictional Plenary of the Second Chamber of the Supreme Court of 19 October 2001, which adopted the criterion of five hundred daily doses and approved a table drawn up on the report of the National Institute of Toxicology of 18 October 2001. Confusing the hashish figure with the marijuana figure transfers to the plant a threshold four times lower, always to the detriment of the person under investigation.

The same agreement contains the decisive rule of computation: the quantity is determined on the base substance reduced to purity, with the exception of hashish and its derivatives. For marijuana, therefore, the THC content is not deducted: the net weight is what counts. That is why the rigour of the weighing, and not the laboratory analysis, decides the boundary of Art. 369.1.5 CP.

That does not make the active-ingredient analysis irrelevant; it simply serves another function. It establishes that what was seized is cannabis in the criminal-law sense —and not industrial hemp— and it allows the number of doses against which gravity is measured to be calculated. A report that merely describes the appearance of the material, without determining its tetrahydrocannabinol content, leaves that assessment without support.

To this is added a delimitation of wider reach. Under the 1961 Single Convention on Narcotic Drugs, the seeds and the leaves that are not attached to the flowering tops are not regarded as cannabis. Judgment 47/2026 of the Supreme Court upheld an acquittal on that basis and warned that broadening the criminal-law concept of a drug without a legislative instrument to support it would breach the principle of legality and legal certainty, without prejudice to any administrative penalty. The line separating personal use from trafficking is examined in detail on our page on self-use versus trafficking.

Setting up an association does not create a ground for excluding criminal liability: what is examined is not the legal form but the activity actually carried on. Courts look at the number of members —once the group ceases to be closed and determinate, the shared-consumption doctrine loses its basis—, at how open admission is, at the proportion between membership fees and the real cost of the cultivation, at advertising and recruitment on social media, and at effective control over the stock held and its destination.

Liability falls chiefly on the managers, and there is a specific sentencing risk on top of that: Art. 369.1.3 CP aggravates conduct carried out in premises open to the public by those in charge of them or their employees. The appearance of legality flowing from registration may support a mistake-of-law defence, but it is assessed case by case and never operates automatically.

Once the offence is ruled out, the matter does not always end there: it may lead to an administrative penalty file, which is a different procedure and leaves no criminal record. Organic Law 4/2015 on the protection of public safety defines two serious infringements of direct interest. Its Art. 36.18 penalises unlawful planting and cultivation in places visible to the public where they do not amount to a criminal offence. Its Art. 36.16 penalises unlawful consumption or possession in public places, roads, public premises or collective transport. Both carry, under Art. 39.1, a fine of 601 to 30,000 euros.

The boundary has immediate consequences, because the visibility requirement is not rhetorical: cultivation inside a home, not perceptible from outside and without a trafficking purpose, does not fit Art. 36.18, and Art. 36.16 requires a public place, which is not the case here. Placing the facts correctly —outside the criminal offence and, where appropriate, outside the administrative infringement as well— is the difference between a file ending in a fine and a prison sentence.

A large share of these cases begins with entry into a home. Art. 18.2 of the Constitution and Arts. 545 ff. of the Criminal Procedure Act allow three grounds and only three: the consent of the occupier given with sufficient information, the reasoned judicial warrant required by Art. 558 of that Act, and flagrancy. A smell noticed from the landing or a striking electricity consumption is none of them: at most it is the basis for applying for the warrant. Once the intrusion is declared unlawful, Art. 11.1 of the Judiciary Act and the doctrine of connected unlawfulness may carry the derived evidence away with it.

The search itself is also governed by rules of practice whose breach can be argued: Art. 569 requires the presence of the person concerned or of whoever lawfully represents them and, failing that, of witnesses. The same goes for the chain of custody of the plant material, where sealing, sample identification, transfer and the laboratory’s receipt records all matter. Any discrepancy between the seizure record and the expert report weighs twice as much when it is the weight that decides the classification.

Limitation periods are calculated on the maximum penalty attached to the offence (Art. 131 CP). The basic form of Art. 368 CP for substances not causing serious harm, with a maximum of three years, becomes time-barred after five years. The aggravated form of Art. 369.1 CP is also time-barred after five, because its maximum of four years and six months does not exceed that figure. Only where Art. 369 bis CP comes into play, with a penalty of up to ten years, does the period rise to ten.