This project centres on the concept of ‘stochastic terrorism’, an under-examined yet growing threat to public security. As described by leading scholars, stochastic terrorism involves ‘the use of mass media to provoke random acts of ideologically motivated violence that are statistically predictable but individually unpredictable’ (Hamm and Spaaij, 2017). Such speech is plausibly related to violent outcomes, and yet falls outside direct forms of incitement. The grey areas brought to light by this particular security risk raise interesting philosophical questions about language, harm, responsibility, rationality, and freedom. Importantly, this project asks at least three overlapping questions about this phenomenon: (1) What is the nature of stochastic language? (2) What are the moral and political problems of limiting stochastic speech? And (3) What should be said about alternative public law solutions? Despite limited academic references to this indirect terrorist method, the topic has become increasingly relevant given recent geopolitical events. For example, the ‘storming of the US Capitol’ on 6 January 2021 saw members of Former President Donald Trump’s supporter base rioting on the US Capitol building and breaching its interior. While Trump’s use of language in the days immediately prior to this insurrectionist event arguably falls short of the standard of incitement, this is likely a candidate case of stochastic terrorism with several recognisable features: incendiary rhetoric from an influential figure; an audience primed and easily goaded into action, aligned with a conspiratorial movement; language-use which has plausible deniability; and an actual security threat as outcome. There is, then, a pressing global and domestic security risk which stands in need of analysis: what is the nature of the problem, and what are the normative ethical worries involved in responding to it? Methodologically, this project is characterised by intersecting jurisprudential and philosophical analyses and fits the Department of Public Law’s tripartite topical matrix, particularly the ‘Fundamentals’ axis. Finally, this project makes important contributions to political philosophy debates on the nature of freedom and value of free speech, and offers insight to those interested in public law preventive concerns about limitation of speech and public security.