A Comparative Analysis from the Perspective of International Criminal Procedure
ABSTRACT
Testimonial evidence has historically occupied a central position in criminal proceedings across all known legal systems. However, the manner in which each system collects, evaluates and safeguards testimony differs markedly depending on the procedural model adopted. These differences reflect distinct philosophical and constitutional conceptions regarding the pursuit of substantive truth, the protection of fundamental rights, and the allocation of powers between the judge, prosecution and defence.
In Spain, the treatment of witnesses and their testimony is structured around the Code of Criminal Procedure of 1882 and the doctrine developed by the Constitutional Court. In common law systems, most notably those of England and Wales and the United States federal jurisdiction, the Federal Rules of Evidence (FRE) of 1975 and the Police and Criminal Evidence Act 1984 (PACE) govern the matter, embodying a fundamentally different conception of testimonial evidence centred on the adversarial system and on cross-examination as the principal mechanism for testing the truth.
I. NORMATIVE FOUNDATIONS AND PROCEDURAL MODELS
The Spanish mixed-inquisitorial system
Spanish criminal procedure follows a mixed model with inquisitorial roots, shaped by the LECrim of 1882, which drew inspiration from the French Code d'Instruction Criminelle of 1808. The trial phase is formally accusatorial, governed by the principles of orality, publicity, immediacy and adversarial contradiction, as enshrined in Articles 229 of the Spanish Constitution (CE), 229 of the Organic Law of the Judiciary (LOPJ), and Articles 680, 686 and 741 LECrim, while the investigative phase retains significant inquisitorial features.
Within this framework, witnesses are under a duty to appear (Art. 410 LECrim), to give evidence (Art. 416 LECrim), and to testify truthfully under oath or affirmation (Art. 434 LECrim), subject to criminal liability for perjury under Articles 458 to 462 of the Penal Code. Exemptions are strictly defined: the privilege against testifying against family members (Art. 416 LECrim) and grounds of professional privilege (Art. 417 LECrim).
The doctrine of the Supreme Court (Tribunal Supremo) on the family privilege under Article 416 LECrim has been the subject of substantial debate, particularly in the context of domestic violence. The courts have oscillated between permitting the reading of prior pre-trial statements where the victim invokes the privilege at trial, and restricting that mechanism so as to prevent the privilege from becoming an instrument of impunity.
The common law adversarial system
By contrast, criminal procedure in the common law tradition rests on the adversarial system, conceived as a dialectical contest between prosecution and defence before an impartial tribunal. The judge neither investigates nor actively examines witnesses; his or her role is essentially that of an arbiter. Evidence is, in principle, that which the parties adduce and control.
This logic is clearly reflected in the United States federal system, where the Federal Rules of Evidence (FRE) of 1975 codify the law of evidence. FRE 601 establishes the general competence of every witness; FRE 602 requires that a witness testify only as to matters within his or her personal knowledge; FRE 603 imposes the requirement of an oath or equivalent affirmation; and FRE 801 to 807 comprehensively regulate the hearsay rule and its exceptions.
In England and Wales, the Police and Criminal Evidence Act 1984 (PACE) governs pre-trial police statements. The Youth Justice and Criminal Evidence Act 1999 (YJCEA) establishes special measures for vulnerable and intimidated witnesses. The Criminal Justice Act 2003 (CJA 2003), Sections 114 to 136, fundamentally reformed the hearsay regime, admitting broad exceptions to the exclusionary rule and modernising a system that had previously been governed by common law principles of difficult practical application.
II. DUTIES AND RIGHTS OF WITNESSES
In the Spanish system
Within this framework, the Spanish system has developed a detailed regime of witness duties and safeguards. The LECrim establishes three fundamental obligations for witnesses under Articles 410 to 434: (i) the duty to appear, non-compliance with which may result in compelled attendance by law enforcement (Art. 420 LECrim); (ii) the duty to testify, subject to the specific exemptions set out in Articles 416 and 417 LECrim; and (iii) the duty to tell the truth, reinforced by the oath or affirmation required under Article 434 LECrim and by the offence of perjury under Articles 458 to 462 of the Penal Code.
Alongside this general regime, Organic Law 19/1994 of 23 December on the Protection of Witnesses and Expert Witnesses in Criminal Cases provides for the concealment of a witness's identity, the possibility of testifying without visual exposure, and the withholding of personal data. This legislation must be interpreted in light of Article 6(3)(d) of the European Convention on Human Rights (ECHR) and the case-law of the European Court of Human Rights (ECtHR) on the right to examine witnesses for the prosecution.
In this regard, the Constitutional Court, in STC 64/1994 of 28 February, held that the use of anonymous witnesses may be compatible with the right to a fair trial (Art. 24(2) CE), provided that: (i) the anonymisation is justified by an objective risk to the witness's safety; (ii) the defence has been afforded the opportunity to examine the witness, albeit without knowledge of his or her identity; and (iii) the conviction is not based solely or to a decisive degree on such anonymous testimony.
The Constitutional Court has further consistently held, since STC 31/1981 of 28 July, the first Constitutional Court ruling on criminal matters and an essential point of reference, that only evidence adduced at trial under the principles of immediacy, publicity and adversarial contradiction can rebut the presumption of innocence guaranteed by Article 24(2) CE. STC 167/2002 of 18 September added that an appellate court cannot convict a defendant who was acquitted at first instance by re-evaluating testimonial evidence that was not heard directly by the appellate court itself, a requirement consistent with the ECtHR's case-law.
In common law systems
In the common law tradition, witnesses enjoy the privilege against self-incrimination. Under the Fifth Amendment to the United States Constitution, no person may be compelled to be a witness against himself in a criminal proceeding. The Supreme Court, in United States v. Balsys (524 U.S. 666, 1998), held that this protection extends only to the risk of incrimination in domestic criminal proceedings, not to the risk of incrimination in foreign proceedings.
Witness competence is the general rule in common law systems. FRE 601 provides that every person is competent to be a witness, abolishing the historical common law exceptions based on a witness's personal interest or religious beliefs. FRE 602, however, requires that a witness have personal knowledge of the matters about which he or she testifies.
As regards the testimony of child victims, the Supreme Court of the United States, in Maryland v. Craig (497 U.S. 836, 1990), held that closed-circuit television testimony by a child victim of sexual abuse was admissible without face-to-face confrontation with the accused. The Court held that the Confrontation Clause of the Sixth Amendment does not invariably require the physical presence of the witness before the accused, provided that there exists a sufficiently case-specific state interest and that the oath, the opportunity to observe the witness's demeanour, and the right of cross-examination are preserved.
III. THE TAKING OF TESTIMONIAL EVIDENCE AT TRIAL
Immediacy, orality and adversarial contradiction in the Spanish model
The taking of evidence at trial is regulated under Articles 679 to 722 LECrim. Witnesses testify in the presence of all parties (immediacy); their statements are oral and public; and both prosecution and defence may examine them. Article 708 LECrim confers on the presiding judge the power to put clarificatory questions, a feature that reveals the residual inquisitorial character of the Spanish system as compared with the common law model.
The principle of adversarial contradiction, derived from Article 24(2) CE and Article 6(3)(d) ECHR, requires that every piece of prosecution evidence must have been capable of being challenged by the defence. The Constitutional Court's doctrine, as consolidated since STC 31/1981, requires that statements made during the investigative phase be ratified and subjected to adversarial testing at trial in order to carry full probative weight as prosecution evidence, save in cases of anticipated evidence (prueba anticipada) or supervening impossibility of attendance.
At the European level, the ECtHR, in Al-Khawaja and Tahery v. the United Kingdom (Grand Chamber, 15 December 2011), established the so-called Al-Khawaja test, comprising three cumulative elements: (i) whether there is good reason for the witness's non-attendance; (ii) whether the statement of the absent witness constitutes the sole or decisive evidence for the prosecution (sole or decisive rule); and (iii) whether there are sufficient counterbalancing factors to enable the accused to mount an effective challenge to that evidence.
This doctrine was subsequently clarified and refined in Schatschaschwili v. Germany (Grand Chamber, 15 December 2015), where the Court held that even where the absent witness's statement does not constitute the sole or decisive evidence, the court must assess whether the counterbalancing factors are adequate.
Cross-examination in common law systems
By contrast, cross-examination constitutes the core mechanism for testing testimonial evidence in common law systems. Unlike the examination of witnesses in civil law jurisdictions, where questions tend to be open-ended, in the adversarial system the lawyer cross-examining a witness called by the opposing party may put leading questions, questions that suggest the answer, a technique that is impermissible during the direct examination of the party's own witnesses.
The constitutional significance of this mechanism was reinforced by the United States Supreme Court in Crawford v. Washington (541 U.S. 36, 2004). In a majority opinion authored by Justice Scalia, which marked a historic turning point, the Court distinguished between: (i) testimonial statements, that is, statements that the declarant knew or should have known could be used in criminal proceedings, which are fully protected by the Confrontation Clause of the Sixth Amendment; and (ii) non-testimonial statements, the admissibility of which is governed by reliability criteria. The practical consequence is that testimonial statements made by an absent witness are inadmissible where the accused has not had a prior opportunity to cross-examine that witness, regardless of the statement's intrinsic reliability.
This doctrinal framework was subsequently supplemented in Davis v. Washington (547 U.S. 813, 2006), where the Court introduced the distinction between statements made for the purpose of establishing facts potentially relevant to a future prosecution, testimonial, and therefore subject to the Crawford doctrine — and statements made during an ongoing emergency, non-testimonial, and therefore admissible without confrontation. The case consolidated two separate matters that perfectly illustrated the tension between the protection of victims and the accused's right to confront his or her accusers.
In English law, the Criminal Justice Act 2003, Sections 114 to 136, reformed the hearsay regime. Section 116 CJA 2003 permits the admission of an absent witness's statement where the witness is unable to attend by reason of death, illness, fear, or other specified grounds, provided the court is satisfied that it is in the interests of justice to do so. Section 114(1)(d) further confers a residual discretion on the court to admit hearsay evidence where it would be fair to do so having regard to all the circumstances of the case.
IV. HEARSAY EVIDENCE: THE POINT OF GREATEST DIVERGENCE
Arguably the most striking difference between the Spanish and common law systems in the field of testimonial evidence is the treatment of hearsay. In common law systems, the hearsay rule, rooted in jurisprudence dating back at least to the seventeenth century, provides that out-of-court statements made by a third party may not be tendered in evidence to prove the truth of their content, subject to exceptions recognised by statute or case-law. The FRE codify more than twenty exceptions in Rules 803 and 804, together with a residual exception in Rule 807.
The Spanish system has no equivalent of the hearsay rule. A hearsay witness, a witness who testifies as to what another person told him or her, is fully admissible as evidence. However, the Supreme Court's doctrine, reiterated in numerous decisions, has held that hearsay evidence carries only secondary probative weight and cannot in itself constitute sufficient prosecution evidence to rebut the presumption of innocence where the direct witness could have appeared but failed to do so.
Accordingly, while the Spanish system does not restrict the admissibility of hearsay evidence in the same terms as the common law, it does limit its probative efficacy. This difference in approach means that both models, despite proceeding from conceptually distinct premises, tend in practice to reach similar outcomes in borderline cases.
V. ANTICIPATED EVIDENCE AND PRE-TRIAL STATEMENTS
Anticipated evidence under the LECrim
This convergence is also reflected in the treatment of anticipated evidence (prueba anticipada). Article 730 LECrim permits the reading at trial of statements taken during the investigative phase where, for reasons beyond the control of the parties, they cannot be reproduced at the oral hearing. This provision functions as a safety valve against the supervening impossibility of a witness's attendance.
Article 448 LECrim makes more specific provision for the taking of anticipated evidence during the investigative phase where there are reasonable grounds for believing that the witness will be unable to testify at trial. For such a pre-trial statement to be valid as anticipated evidence, the Constitutional Court requires: (i) that the impossibility of reproduction was foreseeable at the time the evidence was taken; (ii) that it was taken with full adversarial guarantees, with the participation of the parties and, in particular, with an opportunity for cross-examination by the defence; and (iii) that it be formally introduced at trial by reading or viewing. These requirements derive directly from the ECtHR's case-law and from the constitutional interpretation of Article 24(2) CE.
Furthering the reinforcement of procedural safeguards and the protection of vulnerable victims, Organic Law 8/2021 of 4 June on the Comprehensive Protection of Children and Adolescents (LOPIVI) introduced Articles 449 ter and 707 bisinto the LECrim, regulating the video-recorded forensic interview of child victims of offences against sexual liberty and integrity. Such interviews, conducted during the investigative phase with appropriate safeguards, may be used as pre-constituted evidence (prueba preconstituida) at trial without the need for the child to testify again before the court, thereby reducing secondary victimisation.
VI. PROTECTION OF VULNERABLE AND ANONYMOUS WITNESSES
The Spanish regime
Organic Law 19/1994 constitutes the primary legislation on witness protection in Spain. Article 2 sets out the available measures: anonymity, use of an address other than the witness's actual residence for notification purposes, testimony from behind a screen, prohibition on photography and filming, and police protection. The application of these measures requires an express balancing exercise between witness protection and the accused's rights of defence.
The ECtHR, in Doorson v. the Netherlands (26 March 1996), held that the use of anonymous witnesses may be compatible with Article 6 ECHR where the interests of the defence are weighed against those of witnesses or victims called to testify, provided that the handicaps under which the defence labours are sufficiently counterbalanced by the procedures followed by the judicial authorities.
Subsequently, in Van Mechelen and Others v. the Netherlands (23 April 1997), the ECtHR held that resort to anonymity must be a measure of last resort, and that restrictions on the rights of the defence must not go further than is strictly necessary.
VII. TESTIMONIAL EVIDENCE AND THE PRESUMPTION OF INNOCENCE
Free evaluation of evidence in the Spanish system
The Spanish system connects testimonial evidence with the presumption of innocence through the principle of free evaluation of evidence under Article 741 LECrim, derived from the French concept of intime conviction. There are no predetermined legal rules binding the fact-finder as to the weight to be accorded to any particular piece of evidence. However, this freedom is constrained by the constitutional requirement of reasoned justification (Arts. 24(1) and 120(3) CE) and by the presumption of innocence (Art. 24(2) CE).
STC 31/1981 of 28 July established that only evidence adduced at trial under the principles of immediacy, publicity and adversarial contradiction can rebut the presumption of innocence. STC 167/2002 of 18 September added a further restriction of particular significance: an appellate court cannot convict a defendant who was acquitted at first instance by carrying out a fresh evaluation of testimonial evidence, since to do so violates the right to a fair trial by depriving the accused of the benefit of the immediacy which only the court of first instance enjoyed. This doctrine was subsequently endorsed by the ECtHR in Igual Coll v. Spain (10 March 2009), in which the Strasbourg Court found that a conviction handed down by the Provincial Court (Audiencia Provincial) without holding an oral hearing violated Article 6 ECHR.
VIII. COMPARATIVE ANALYSIS: CONVERGENCES AND DIVERGENCES
Adversarial contradiction as a shared guarantee
Both systems share a common core: the right to examine witnesses for the prosecution, enshrined in Article 6(3)(d) ECHR, the Confrontation Clause of the Sixth Amendment to the United States Constitution, and Article 67(1)(e) of the Rome Statute. The difference lies in the mechanism: the common law system relies on cross-examination as the primary tool for testing witness credibility; the civil law system relies on judicial immediacy reinforced by adversarial examination by the parties. Both pursue the same objective through different techniques that reflect the different allocation of roles between judge, prosecutor and defence counsel.
Hearsay as the point of deepest divergence
The most fundamental difference manifests itself in the treatment of hearsay. The common law hearsay rule has no continental equivalent. Spain does not exclude hearsay evidence a priori, but limits its probative weight. This difference stems from the distinct degree of confidence placed in the jury as opposed to the professional judge: the hearsay rule arose historically to protect lay juries from evidence of doubtful reliability that they might be liable to misapprehend, a concern that does not arise to the same degree before technically trained judges capable of assessing the weight of hearsay testimony. The absence of the jury in the Spanish system thus renders the automatic exclusion of hearsay functionally unnecessary.
IX. CONCLUSIONS
The comparative analysis identifies a structural divergence that is not merely technical in nature, but reflects distinct conceptions of who controls the evidence and how procedural truth is to be achieved.
The deepest difference lies in the distribution of roles between the judge and the parties. The Spanish system assigns the judge an active role in the examination of testimony: immediacy is simultaneously a guarantee of reliability and a constitutional constraint. The common law system entrusts that function to the parties through cross-examination, relegating the judge to an arbitral role.
Within this framework, the hearsay rule is the clearest expression of this divergence. Its absence in the Spanish system is not a lacuna but a logical consequence of the fact that the jury is not the ordinary decision-making body. The rule originated to protect lay juries from evidence that is difficult to weigh; before technically trained judges, that protection is unnecessary. The Spanish system addresses the same problem through evaluation rather than exclusion.
The differences between the two models are not, therefore, historical anomalies awaiting correction, but coherent expressions of distinct constitutional choices regarding the allocation of power within criminal proceedings.
