Crooked as a dog's hind leg simile
Very dishonest and deceptive
Don't play cards with Tom. He's as crooked as a dog's hind leg.
I advised Mary shouldn't put her trust in Tony. He's as crooked as a dog's hind leg.
To be dishonest or deceptive and no one can believe
Try to avoid to change something because doing something else could make things worse
I could have changed my answer, but I decided to leave well enough alone.