His own ego would eventually turn him to crime: leading him into diamond smuggling, which is the main focus of the episode "To Hull and Back" and a strong part feature of the plot to "The Class of '62".

As well as the main characters making clear their thoughts and attitudes towards him, his own colleague PC Terry Hoskins reveals that even his peers in the police service reject him, and Slater admits during the episode to having arrested his own father in the past (for riding a bicycle with a defective rear light), alienating him from his family.

His position of authority within the police has been exploited a number of times to successfully smuggle diamonds into England, and over the course of the episode he almost succeeds again, only to be thwarted by Hoskins who drives him into a sting and lands Slater with a five-year prison sentence.

Slater's final appearance in character was in "The Class of '62", in which he has been paroled from prison after three and a half years of his five-year sentence and returns to Peckham, setting up a school reunion to which Del, Boycie, Trigger, and Denzil are invited, with Rodney joining them.

The character of Slater was based on another corrupt police officer in Sullivan's previous series Citizen Smith, PC Tofkin played by John Tordoff.