A just culture is meant to balance learning from incidents with accountability for their consequences. All the current proposals for just cultures argue for a clear line between acceptable and unacceptable behavior. This alone, however, cannot promote just culture as it falsely assumes that culpability inheres in the act, bearing immutable features independent of context, language or interpretation. The critical question is not where to draw the line, but who gets to draw it. Culpability is socially constructed: the result of deploying one language to describe an incident, and of enacting particular post-conditions. Different accounts of the same incident are always possible (e.g. educational, organizational, political). They generate different repertoires of countermeasures and can be more constructive for safety. The issue is not to exonerate individual practitioners but rather what kind of accountability promotes justice and safety: backward-looking and retributive, or forward-looking and change-oriented.