Which aspect is crucial in maintaining chain of custody?

Maintaining the chain of custody is essential for ensuring that evidence remains admissible in court and has not been altered or tampered with. Documenting each transfer of evidence creates a clear record that tracks who has handled the evidence and when it was handled. This accurate documentation reinforces the integrity of the evidence by providing a detailed history of its custody, which can be vital in a legal context. Each entry in the chain of custody log serves as a safeguard against challenges to the evidence's reliability, giving it greater weight during legal proceedings.

Restricting access to evidence is indeed important but primarily serves as a preventative measure rather than a record-keeping function. It does not replace the necessity of thorough documentation during the transfer process. Recording only the evidence that is used in trial disregards the importance of accountability for all evidence, regardless of its outcome. Proper storage in multiple locations could introduce complexity and increase the risk of losing track of evidence, therefore making documentation far more critical than such practices.