In what scenario would a victim's social media be useful in a death investigation?

The use of a victim's social media in a death investigation can be particularly valuable for gathering potential motives or connections to suspects. Social media platforms often serve as a reflection of a person's relationships, interactions, and activities. By analyzing posts, comments, and connections, investigators can uncover information about the victim's personal and professional relationships, interactions with others, and possible conflicts or tensions that might point to motives for murder or harm. This information can provide crucial leads in identifying suspects who may have had a reason to harm the victim, thus aiding the overall investigation process.

The other scenarios, while they have their own relevance, do not leverage the true strengths of social media. Tracking geographic movements is better achieved through location data and cellphone records rather than social media, which may not always provide accurate geolocation information. Finding a timeline of the weather is typically researched through meteorological data rather than social media content. Identifying witnesses might also be done through social media interactions, but it does not capture the primary value of motive establishment as effectively as the correct choice does.