Legal Question in Civil Litigation in California

As a document created for the activities of the buiness of law enforcement and kept in the normal course of the entity's business activities, an incident report should qualify as a business record. But a record about someone unrelated to the case has no relevancy to the case so the police duld move to quash the subpoena. Those records are also probably confidential so it would have to be proven first that the records are relevant. If you wanted to impeach a witness at trial with a police report saying that they had stopped him, a judge would rule that it is inadmissible as being irrelevant, to prejudical to allow in, etc.