Criminal Litigation: Evidence (Part 1)

Both the law governing the use of corroborative or supporting evidence and the application of the ‘Turnbull Guidelines’ in cases including disputed evidence of eye witness identification, ensure that the court reaches its verdict on the basis of ‘reliable’ evidence.

Corroborative evidence is evidence which supports or confirms other evidence in the case. Evidence that needs to be corroborated is generally considered unreliable.

Where witness evidence is questionable in some respect, a corroboration warning might e called for. This alerts the jury/magistrates of the dangers of relying solely on the evidence of that particular witness and the need for evidence supporting what the witness said.

Encountered in two situations:

• Corroborative evidence required as a matter of law: there are few examples e.g. Perjury (s13 Perjury Act 1911), treason (s1 Treason Act 1795), Speeding (s89 (2) Road Traffic Regulation Act 1984).
• A corroborative warning is entirely discretionary and will depend on the facts and circumstances (R v Makanjuola).

The requirements for corroborative evidence are laid out in R v Baskerville (1916), which states:

1. The evidence should be admissible in its own right.
2. It must be independent of the evidence to be corroborated.
3. It must implicate the accused in a material way with the crime charged.

The Turnbull Guidelines are important in trial where the defendant claims to be the victim of mistaken identity. Disputed evidence of eye-witness identification is treated with caution in order to avoid a miscarriage of justice.

The guidelines require:

1. The judge to make a qualitative assessment of the evidence of identification.
2. If the evidence is poor and unsupported he must direct an acquittal.
3. If the evidence is poor but supported or the evidence of identification is good the judge can leave it to the jury but must stress the need for caution.
4. Where the evidence is poor but supported the judge must point out the evidence that is capable of providing the support.

The judge must explain why there is a special need for caution associated with such evidence. He should invite the jury to consider the circumstances in which the identification of the defendant was made and point out any weaknesses i.e. failure to make a positive Id, breach of code D or inconsistencies between witnesses.

Failure to give a Turnbull Warning will provide the defendant with grounds for appeal.

Opinion Evidence in criminal proceedings is inadmissible with two exceptions:

1. Facts personally perceived by the witness. The witness giving evidence of opinion which he has personal knowledge and experience that does not require expertise or training.
2. Expert witnesses may give his opinion on an issue that goes beyond the ordinary competence of the court.

Duties of an expert are set out in the Criminal Procedure Rules Part 33:

• An expert must give unbiased opinion on matters.
• This duty overrides any obligation to the person from whom he receives instructions or is paid.
• The duty includes an obligation to inform all parties & the court of his opinion if it changes from the report.

Procedure for admitting expert evidence are contain in s81 PACE 1984 and Part 24 and 33 Crim PR.

Where either party proposes to rely on expert evidence it must provide the other party with a written statement of any findings or opinion including any test, calculation or procedure used to base his opinion.

If the defendant obtains an unfavourable report, the defence are under no obligation to disclose it as it is protected by legal professional privilege.