Which measure can indicate that a police firearm is secured in the cruiser?

The measure that effectively indicates a police firearm is secured in the cruiser is when the service weapon is holstered. When a firearm is holstered, it is kept in a designated place designed for the weapon, ensuring it is not easily accessible unless needed by the officer. This practice enhances safety by minimizing the risk of accidental discharge or unauthorized access, reinforcing the secure handling of firearms during transit in a police vehicle.

While other options refer to safety features or readiness, such as having a manual safety engaged or a trigger lock enabled, these are more relevant to firearm handling practices outside of the cruiser. They do not directly address the status of the weapon while secured within the vehicle itself. The concept of a "cruiser ready AR" implies readiness for immediate use, but it does not specifically indicate that the firearm is secured, making it less applicable in this context. Thus, having the service weapon holstered is the most appropriate measure to indicate that the firearm is appropriately secured in the cruiser.