The OPCW establishes in Fact-Finding Missions (FFM), if alerted to the usage of toxic chemicals as weapons, whether such an incident took place and what substances were used. In order to do so, the FFM obtains a variety of information from multiple sources including photographs. This article addresses the role of photography as a tool to record and document subject matters of war and conflict, with a particular focus on the deployment of chemical weapons. Firstly, the origins and abilities of war photographs are summarized, followed by an introduction to photographs as pictorial messengers. This section is contextualized by a short history of war photographs. Secondly, the ethics of war photographs are investigated, leading to the complex issues of the coverage of chemical warfare terrorism and the advent of AI-generated photographs.