About once a month, according to my tracker, some confused elderly person will put one of these alternatives into Google, hoping to get the words of a song by Gilbert and Sullivan. The seeker ends up here and finds both the words and a link to a duo singing the first verse, as well as the information that it is not by G&S at all, but by Offenbach. In this song, the public guardians are a pair of corrupt cowards.
Obviously the poor old dears (most of them, oddly, are Australian) who think it's by G&S are getting it mixed up with When a Felon’s Not Engaged in his Employment, from The Pirates of Penzance. which is sung by a whole squad of honest and caring coppers. They can hear the first verse of this by clicking with their palsied fingers on this link and going down to Sample No 16.