dishonest or morally wrong
murky - shady
‘Murky’ was originally used to describe water that is dark and dirty and therefore difficult to see through. The term has since been adapted to describe a complicated and unpleasant situation in which the facts or morality of it are not clear.
The politician is thought to be involved in the murky world of the international arms trade.
I’m not sure I would want to go into business with Peter. I think his past is a lot murkier than he lets on.
The documentary helped to shine a light on the murkiness of the finance industry.