How should the magazine of a firearm be handled if removed from the weapon?

When handling a magazine that has been removed from a firearm, properly marking it is essential for several reasons. First, marking the magazine helps to ensure it can be accurately tracked and identified later on. This is particularly important in contexts such as investigations or evidence handling, where maintaining a clear chain of custody is necessary.

By marking the magazine, law enforcement personnel can prevent confusion and avoid mixing it up with other items, which contributes to the integrity of the evidence collection process. Additionally, this practice can serve as a useful reference for investigative records.

The other choices do not align with standard operating procedures for firearm handling. Discarding the magazine would eliminate a crucial piece of potential evidence. Keeping the magazine in the firearm could lead to complications, especially if the firearm needs to be stored or transported safely. Cleaning a magazine before packaging is typically not a preferred procedure, as it may alter the condition or integrity of the evidence. Thus, marking the magazine upon removal is the recommended approach.