Without a leg to stand on phrase
Without any proof, support, or good reasons for one's viewpoint, argument, or actions.
Now that the detective has exposed your false alibi, you are without a leg to stand on.
When no witnesses came with me, I knew I was without a leg to stand on.
Listen, you can't sue them for the damages without a leg to stand on.
This metaphoric idiom transfers lack of physical support to arguments or theories. [Late 1500s]
Be embarrassed and ashamed when one has been defeated or failed
After losing that game, she had her tail between her legs.