DUBIOUS

[adjective] - thought not to be completely true or not able to be trusted, or feeling doubt or uncertaintyThese claims are dubious and not scientifically proven.He has been associated with some dubious characters.I'm dubious about his promises to change his ways.Ruth Ellis has the dubious (= bad) distinction of being the last woman to be hanged in Britain.Blake has the dubious privilege of being perhaps the greatest artist not to be represented in the museum.