What action may police take to preserve evidence of an offence?

To preserve evidence of an offence effectively, police can take preventive measures to stop any potential tampering. This action is crucial because once evidence is altered or destroyed, the integrity of the investigation can be compromised, and it may negatively impact the prosecution's case. By stopping the suspect from tampering with evidence, the police ensure that the evidence remains in its original state, which is essential for establishing the facts of the case.

Documenting evidence, such as through photographs or reports, while valuable, does not actively prevent tampering during the investigation. Furthermore, merely removing items from public view does not guarantee that evidence is preserved if individuals still have the opportunity to affect it before it is officially secured. Therefore, the action of stopping any form of tampering directly addresses the immediate need to maintain evidence, making it the most appropriate and effective response in the context of preserving evidence of an offence.