How Misinterpretation Can Affect Criminal Defence Strategy

A defence strategy is only as sound as the instructions it is built on. For a non-English-speaking defendant, every instruction, every first account and every proof of evidence passes through an interpreter. When interpretation fails, it rarely announces itself — it surfaces months later as an "inconsistency" in cross-examination, an admission the client says they never made, or advice the client did not understand. This article maps where the damage occurs and what defence solicitors can do about it.

Four points where misinterpretation distorts the defence

1. The first account

What the client says at the police station — in consultation and in interview — anchors the case. A mistranslated time, place or relationship in the recorded interview becomes prosecution material. If the client later corrects it, the correction reads as a changed story, and the jury may be invited to draw exactly that conclusion. Adverse inference risk compounds the problem: a client who did not genuinely understand the caution, or the advice to make no comment, cannot make an informed choice about silence. See The Role of an Interpreter in Police Station Interviews.

2. Instructions and the proof of evidence

Defence strategy decisions — plea, basis of plea, whether to give evidence, alibi notices — depend on precise instructions. Arabic dialect terms for family relationships, debts, threats and honour carry meanings that generic interpreting flattens. A proof of evidence built on flattened instructions can commit the defence to a version of events the client never gave.

3. Apparent inconsistency between stages

Different interpreters at the police station, the conference and the trial will render the same Arabic phrase differently — each defensibly, but not identically. The prosecution then has three English versions of one account. Interpreter continuity removes this manufactured inconsistency at source.

4. The trial itself

A defendant follows the evidence against them through the dock interpreter, and gives evidence through the witness-box interpreter. Summarised or lagging interpretation means the defendant cannot give timely instructions on prosecution evidence — a fair-trial issue in itself. And in cross-examination, a single mistranslated answer can hand the prosecution a gift no re-examination fully repairs.

The legal consequences

Where interview interpretation was materially defective, the defence may seek exclusion of the interview under section 76 (reliability of confessions) or section 78 (fairness) of PACE, supported where necessary by an independent transcript and re-translation of the recording. Interpretation failures at trial can found applications to discharge, and in serious cases appellate challenge. But litigation after the fact is the expensive remedy; the inexpensive remedy is preventing the error.

Safeguards to build in from day one

• NRPSI registration, verified. Check the interpreter's number on the public register; registration brings assessed legal-interpreting competence and a binding code of conduct.
• Dialect-match, specified at booking. Yemeni, Sudanese, Syrian, Iraqi and Gulf Arabic are not interchangeable. Specify the client's dialect, and confirm mutual comprehension at the first attendance.
• Continuity. Instruct one named interpreter across consultation, conference and hearing wherever possible.
• Preparation. Share the case papers. An interpreter who has read the disclosure renders names, dates and technical terms consistently with the record.
• Contemporaneous notes. Record any comprehension issue, with time and context, the moment it arises.

The strategic point

Interpretation quality is not overhead — it is evidence integrity. Every pound saved on a cheaper, unverified interpreter is borrowed against the risk of a distorted record, and the interest is paid at trial.