The answers may be facts from these questions:
1. Were all expended cartridge cases on the scene collected?
2. By whom?
3. Have they been securely retained?
4. Where were they located when collected?
5. What calibers were they?
6. How many?
7. Do they match the wounds of the dead and wounded?
The above would normally be designated as evidence.
Looks like it will be awhile before we see all the reports.
Lack of answers to those questions is normally known as incompetence.