Art. 1 CP
Criminal guarantee
No act is an offence unless provided by a law prior to its commission.
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Theory of crime · Articles 1-4 CP · Throughout Spain
The principle of legality
No offence or penalty without a prior, written and precise law: the first guarantee of any accused.
The principle of legality (Arts. 1-4 of the Criminal Code, Art. 25 of the Spanish Constitution) is the foundation of criminal law: no one may be convicted for an act not defined as an offence by a prior, written, precise and strictly interpreted law. It is a first-order line of defence.
In brief. the principle of legality (nullum crimen, nulla poena sine lege) requires a prior law (lex praevia, non-retroactivity, Art. 2), written (lex scripta), certain (lex certa, precise definition) and strict (lex stricta, no analogy in malam partem, Art. 4). The more favourable criminal law, by contrast, is retroactive (Art. 2.2). These guarantees ground many lines of defence.
Key facts
25 CE
Article of the Constitution enshrining the principle of criminal legality.
2.2
Retroactivity of the criminal law more favourable to the accused.
24h
English-speaking lawyer, control of criminal guarantees throughout Spain.
The fundamental guarantee
No conviction without a prior law. The act must be defined as an offence by a law in force when it was committed. Retroactively creating an offence or later aggravating a penalty is prohibited (Arts. 1 and 2).
The criminal law is strictly interpreted. Article 4 prohibits application by analogy to the detriment of the accused: the judge may not extend a criminal type to acts it does not expressly provide for.
Favour, however, is retroactive. Where a later law is more favourable, it applies to earlier acts, even already tried (Art. 2.2) — a concrete lever where the Criminal Code is reformed.
What we invoke
The guarantees of legality
Art. 2.1 CP
Non-retroactivity
No penalty applies to an act not criminalised when committed.
Art. 2.2 CP
Favourable retroactivity
The more favourable criminal law applies retroactively to the accused.
Art. 4.1 CP
No analogy
Prohibition of applying the criminal law by analogy against the accused.
Art. 25 CE
Constitutional rank
Legality is protected by the Constitution and the amparo appeal.
Lex certa
Precision of the type
Requirement of clear definitions; vague types can be challenged.
Art. 3 CP
Jurisdictional guarantee
Penalty imposed only by the competent court, by the legal procedure.
Art. 3 CP
Enforcement guarantee
Enforcement of penalties in the forms and conditions provided by law.
Art. 9 CE
Legal certainty
Prohibition of arbitrariness and guarantee of foreseeability of the law.
Scope
Overview of the guarantees
| Guarantee | Basis | Content | Effect for the defence |
|---|---|---|---|
| Lex praevia | Art. 2.1 | Non-retroactivity | Act not criminalised at the time |
| Lex favorable | Art. 2.2 | Favourable retroactivity | Applying a milder reform |
| Lex scripta | Art. 1 | Formal law | Custom excluded |
| Lex certa | Art. 25 CE | Precise type | Challenging vague types |
| Lex stricta | Art. 4.1 | No analogy | Excluding an extension |
| Jurisdictional guarantee | Art. 3 | Competent court | Nullity of irregularities |
| Enforcement guarantee | Art. 3 | Legal forms | Control of enforcement |
| Legal certainty | Art. 9 CE | Foreseeability | Prohibition of arbitrariness |
Indicative elements based on the Spanish Criminal Code and Constitution. Application depends on the specific case. This overview does not replace a lawyer’s analysis.
Our difference
Legality, the defence’s first line
Many cases are won on legality. A vague criminal type, an analogical application, criminalisation later than the acts or a retroactively aggravated penalty are all violations that may lead to acquittal or nullity.
We also exploit favourable reforms. Where a reform of the Criminal Code softens a penalty, Article 2.2 requires its retroactive application — including to convictions already handed down.
01
Control of the law applicable at the time of the acts
02
Challenging vague or analogically applied criminal types
03
Invoking the later, more favourable criminal law
04
Amparo appeal where legality is breached
How we act
A structured defence at every stage
Phase 01
Analysis of the legality of the type applied
Phase 02
Control of the law in force at the time
Phase 03
Plea on strict interpretation
Phase 04
Appeals and, where appropriate, constitutional amparo
Who we represent
Very different situations
D
People under investigation
People accused on the basis of a vague type or an extensive interpretation.
C
Convicted persons
People who may benefit from a later, more favourable reform.
E
Companies
Companies facing economic offences with blurred contours.
F
Families
Relatives seeking to understand the guarantees applicable to the proceedings.
Related
Related pages
FAQ
What you should know
What does “no offence without law” mean?
That no act may be punished unless it was defined as an offence by a law prior to its commission (Arts. 1-2 CP, Art. 25 of the Constitution).
Can the criminal law be retroactive?
Only where it is more favourable to the accused (Art. 2.2). Retroactive criminalisation or aggravation is prohibited.
May the judge reason by analogy?
Not against the accused. Article 4 prohibits analogical application of the criminal law in malam partem.
What is taxatividad?
The requirement of precise criminal types (lex certa). A vague or indeterminate offence may be challenged as contrary to legality.
Does a milder reform benefit convicted persons?
Yes. Under Article 2.2, the later more favourable law applies even to already-tried acts, which may justify a review of the sentence.
How are these guarantees asserted?
Through nullity motions, appeals and, where appropriate, a constitutional amparo. The firm assists 24/7 in Spain.
Speak to a criminal lawyer
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Criminal defence in English before the courts of Alicante and the rest of Spain, for residents and for visitors who have flown home.
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