Definition: Given the Question and Answer pair, detect whether the answer is acceptable or not. Denote acceptable answer as "yes", otherwise denote as "no". An acceptable answer is consistent with the context in question, detailed, long, and uses general knowledge of English. Answers that are not definite and suggest a variety of options are not acceptable answers.
Input: Question: What is the idiom for a situation that "If people-in-authority don't follow their own set rules, then what can one expect from rest of us" in similar examples given below in different settings: When HR themselves are tardy, undisciplined then what can you expect from the employees (punctuality and discipline)? When traffic police themselves are offending (driving without belts, smoking while driving) what can you expect from the vehicle driving community in the city? When parents themselves are undisciplined (smoking in front of children), what can you expect from the children themselves? When the management is insincere, what can you expect from their staff? 
Answer: While not an exact fit (because it doesn't necessarily involve figures of authority), what about the following: If they don't practice what they preach why should we? from def: To do the things that you advise other people to do: He's such a hypocrite! He never practises what he preaches. (Cambridge) Also, while not an idiom, hypocrite fits as well.

yes