The Prison Prep School Murder Case File 5 - S1-E14
Stupidity: When the Puppeteer is shot, like any good villain he's actually wearing a bulletproof vest. However, a bulletproof vest is not a magical forcefield that neutralizes kinetic energy; this guy barely flinches when hit. Neither are flames; his fire trick raises a literal firewall, but firewalls are not literal walls, they do not stop bullets. The policemen could easily keep shooting through it (he throws a glove at Kindaichi through it), but they just do not, for no reason.