What is the right to silence?

The caution says it all: "You are not obliged to say anything, anything you say may be used as evidence against you, and refraining from answering may strengthen the evidence against you." A suspect has a full right to silence: you may decline to answer one question, several, or all of them. Silence cannot be punished, and a version of events cannot be forced out of you.

But silence is not free. A version first heard at trial, having been withheld during the investigation, is treated as a "late version" and carries little weight. At trial itself, a defendant's refusal to testify can serve as corroboration of the prosecution's evidence (Criminal Procedure Law, section 162). That is why the choice between silence, speaking, or a mix of the two is the central decision of preparing for an interrogation.

Silence is different from other conduct. Refusing to hand over a phone or password is a right, not an offence (the Urich ruling). Deleting messages, on the other hand, is obstruction of justice. And a "friendly" chat with the investigator in the corridor is part of the interrogation, even without a caution.

What a lawyer does: in the preparation meeting, works out what the suspicion is, what the police probably already know and what your account is, and advises where silence protects you and where it hurts. During the interrogation itself you may ask for a break and consult again before answering.

Source in law: Criminal Procedure (Evidence) Ordinance, section 2; Criminal Procedure Law [Consolidated Version], 5742-1982, section 162