Training-Free Policy Violation Detection via Activation-Space Whitening in LLMs. - Oren Rachmil; Roy Betser; Itay Gershon; Omer Hofman; Nitay Yakoby; Yuval Meron; Idan Yankelev; Asaf Shabtai; Yuval Elovici; Roman Vainshtein (CoRR, 2025)