This article is a Stub.
There's fairly well-documented cases and study of the effect that witnessing people being abused or traumatized is in itself traumatic.
This is different from vicarious trauma when someone takes on guilt or shame from hearing or vividly imagining/picturing or empathizing with survivor accounts. This involves actively witnessing a situation-in-progress in some way. Witness trauma does not need to be visual contact, being in the same room, etc. So this includes hearing something traumatic happening to someone else, for example.
Witness trauma is acknowledged as a specific type of trauma in Melody Beattie's work Facing Codependence (1989 & 2003)1 and adds a layer of "survivor" guilt to the situation for the witness in addition to guilt over not being able to defend the victim, as well as fear/avoidance issues of not wanting to be hurt or victimized oneself.
People may see siblings being traumatized, or parents involved in domestic violence, may witness a car accident or other traumatic situation, or in the case of folk who are multiples, we may have witness abuse from being co-conscious and unable to help one another due to being locked out of front, or being in flight mode and avoiding being the victim while paradoxically wishing we could save the headmate receiving the trauma.
Also note: there's a lot of complications around witness trauma and feeling responsible for siblings or headmates who are abused — and a lot of potential for shame New & anger around those issues. These complications can lead to angry/vehement denial and it can be a huge obstacle to intimacy as shame feelings get stirred up even in normal interactions between the victim & the witness.
Some abuse involves being made to witness abuse, in which case it could be called "witness abuse". Other times the witnessing itself is not a part of the intended abuse, even though the situation may be intentionally abusive towards someone else. This may also play a role in RA/SRA when traumatic & adverse activities are done in groups.
A further complication in witness trauma is the guilt over feeling relieved that you are not the target (this time?) — coupled with the shame of not being able to save the victim.