Is there a word in English that describes the behavior of someone who realizes they are being monitored by some authority or supervisor, and as such, are acting on "their best behavior"? For instance, a school yard bully might act like a sweet, innocent child and treat other children with kindness if she knows that the teacher is watching.

I'm looking for a word that describes this type of phony "goody-two-shoes" type behavior. Sanctimonious and pious are close, but both imply that the portrayer considers herself to be morally superior, which doesn't fit this scenario. Insincere is spot on (its fake/feigned behavior), but is too generalized and doesn't apply specifically to the above scenario where an actor is pretending to be a goody-two-shoes because they fear repercussion from some authority.

Another example: I might pretend to be working diligently if I know my boss is watching me closely, but the minute he goes on vacation I slack off and stop working.

Any ideas?

Update

Despite the resilient efforts of this wonderful community's denizens to help me find the one word in the English language that describes this type of scenario, all attempts have fallen just a wee bit short.

As such, I am proposing a new word be added to the English language, if no one minds.

snaperly: describing deceitful behavior conducted so as to conserve impunity

If no one minds, I think I'll use this word and add it in. Tangentially, how do I add this word to English?