Illegally or improperly obtained evidence

To successfully secure a conviction, the prosecution must obtain evidence that proves the defendant’s guilt beyond doubt. However, the prosecution may be tempted to resort to improper means to gather evidence in support of their position, especially if obtaining evidence in conventional ways proves unfruitful. It is for the trial judge to rule on matters of admissibility of the evidence (in the jury’s absence).

Illegally obtained evidence is evidence obtained during an illegal search or seizure of goods, or entrapment. Evidence obtained improperly may, for instance, be evidence obtained in breach of the Police and Criminal Evidence Act 1984 (PACE) or where information is surreptitiously downloaded from a computer.

In criminal proceedings, all relevant evidence presented is prima facie admissible – the UK courts have adopted an inclusionary approach towards evidence in order to favour the victim and ensure a fair trial. The rationale behind this approach is that the court considers the primary aim of the justice system to be the discovery of the truth and is a priority above the protection of the accused’s right to private life.

Nevertheless, the courts have a discretion under section 78 of PACE to exclude prosecution evidence which lacks relevance and which may otherwise endanger the fairness of a trial. Exclusion under s78 typically relates to the way in which the evidence was obtained.

The fairness of a trial could be endangered by the admission of unreliable evidence. English case law distinguishes between illegally obtained real and confessional evidence. Improperly obtained confession evidence, such as confessions obtained under torture contrary to Article 3 ECHR, can be seen as inherently unreliable. On the other hand, real evidence – even if improperly obtained – such as evidence obtained through searches or covert listening devices without a warrant, will remain reliable.

The general rule is that real evidence is generally included, unless its admission would adversely affect trial fairness. The judge will exercise discretion to exclude evidence under s78 PACE where the evidence would have such an adverse effect on the fairness of the trial that it ought not to be admitted. The fact that there has been a breach of PACE or other police codes of practice will not, of itself, mean the evidence will be automatically excluded.

Although the accused cannot usually prove that the admission of improperly obtained evidence would endanger the fairness of their trial and thus prevent its admissibility – it may be possible to claim compensation for breach of convention rights.

When real evidence has been excluded, this is usually a result of a breach of a suspect’s right against self-incrimination, or due to gross and deliberate police misconduct.

On the other hand, confession evidence will generally be excluded under the Police and Evidence Act 1984 as it is unreliable and likely to affect the fairness of the proceedings.

Where confessions are at issue, a confession must be excluded under PACE if it is represented to the court that the confession was obtained by oppression, or as a result of ‘anything said or done’ which was likely in the ‘circumstances existing at the time’ to render the confession unreliable; or the court of its own motion requires proof that the confession was not so obtained.

The prosecution does not need to prove the admissibility of a confession unless the defence represents to the court that it is inadmissible under s76 PACE (ie. because it would be unfair to adduce it).

Real evidence obtained in breach of an accused’s right to private life under Article 8 ECHR, for instance, through covertly obtained video or audio recordings, remain admissible in criminal proceedings and does not violate the accused’s right to a fair trial under Article 6 ECHR: the European Court of Human Rights has held that the right to private life is not an absolute right.

However, the courts decide cases in a way that is compatible with the Article 3 prohibition of torture, by maintaining a strict exclusionary stance to confession evidence obtained through torture, regardless of the reliability of the evidence. This reflects the fact that the Article 3 prohibition of torture is an absolute right, and ensures conformity with the accused’s fundamental right against self-incrimination. It also serves as a means of deterrence, to ensure torturers are not rewarded for their conduct.

Section 8 of the Human Rights Act provides a right for defendants to claim damages for police breaches of the law or of rules which breach their Convention rights.