bystander

This term describes a person who is physically present during an event but remains detached from the action. It carries a neutral tone when referring to a witness in a legal or factual sense, simply denoting presence without participation. In social or moral contexts, the word often acquires a negative connotation, implying passivity or a failure to act in the face of injustice or emergency. This usage highlights the tension between the ability to intervene and the decision to remain a spectator.