If it is believed that someone has committed suicide with a gun, what is the most important evidence to preserve at the scene?

The preservation of hands or the weapon is crucial in a suspected suicide with a gun scenario because it directly relates to determining the events surrounding the incident and the actions of the deceased prior to death.

Evidence from the hands can reveal critical information; for example, gunshot residue (GSR) testing can ascertain whether the individual discharged a firearm shortly before death. This can help substantiate or refute the suspicion of suicide. Preserving the weapon is also important since it connects the individual to the act; however, focusing on the hands can provide a more immediate biological link to the shooting event itself.

While the weapon is significant because it can be analyzed for fingerprints and ballistics, the condition of the victim's hands often plays a more vital role in quickly establishing what occurred. Other elements like the victim's belongings and witness testimonies can provide context but are secondary to the biological evidence derived from the hands and the weapon in determining the nature of the death.