Ghosts are characters featured in Murdered: Soul Suspect. They are metaphysical manifestations of the souls of deceased people or animals. They appear as they did when they were alive, however they are capable of shapeshifting, teleporting, and have a slight transparency to them. Also, however they died is imprinted on their translucence.

Ghosts are incorporeal beings that cannot be perceived by humans. Because they do not possess a physical body, they are capable of passing through most walls and objects, as they are already dead they are truly immortal and can never die. Exterior walls act as barriers to ghosts, however, because the citizens of Salem habitually christen their buildings, preventing spirits from passing through freely.

As a ghost, Ronan has the ability to possess humans or animals and access their senses of sight and hearing, as well as look into their minds and access their memories. Although is unclear whether these abilities are exclusive to Ronan O'Connor, all ghosts have special powers: some common to all, others related to personal characteristics or activities they had practiced when alive.