A high-ranking state firefighter with 24 years of experience was compelled to resign last month because his department believed he helped a fire captain cheat on a test that the captain failed. Jeff Isaacs’ ouster as an assistant chief for the department’s Fresno unit is a sign of the tough line Cal Fire has taken on discipline since a 2014 investigation revealed sex-related misconduct and inappropriate drinking at its fire academy. It’s building up a professional standards program while simultaneously enhancing its resources for internal investigations. For a moment, the charge that Isaacs helped someone cheat also threatened promotions for dozens of captains who had taken an exam in November 2016 to promote to battalion chief.