Once you've assigned an investigator to a case, the system sends a new Case Assignment Notice to the investigator's email address. By default, this is the only means of alerting an investigator that they have been assigned to a case.
If you'd like to make sure your investigators have accepted the assignment and are prepared to work, consider enabling case assignment confirmations. This handy feature prompts investigators to confirm the receipt of their assignments, which then updates the system with the date and time of the confirmation. Using confirmations allows managers to verify that investigators are aware of their case assignments and are prepared to work, which can eliminate the need for follow-up emails or phone calls.
Auditing of assignment confirmations can be done via the Assigned tab of any case, or en masse via the Case Assignment Audit report.