distrustful having or showing distrust; "a man of distrustful nature"; "my experience...in other fields of law has made me distrustful of rules of thumb generally"- B.N.Cardozo; "vigilant and distrustful superintendence"- Thomas Jefferson
suspicious -
not as expected; "there was something fishy about the accident"; "up to some funny business"; "some definitely queer goings-on"; "a shady deal"; "her motives were suspect"; "suspicious behavior"