can't/couldn't very well do something
can't very well (do something)
Cannot or should not do something because it would be inappropriate or unreasonable. I barely know the guy, so I can't very well ask him to do me this massive favor!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
can’t/couldn’t very well do something(informal) used to say that something is not the right thing to do: You can’t very well change the arrangements now. It’s too late to inform people.
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