If they overstay their visa, they are not legal...
Are you against legal immigration?
If they overstay their visa, they weren't good applicants in the first place.
I'm all for 'legal' immigration, if it had any oversight. USCIS admits to approving thousands of applications they they didn't review the files on, because they can't find them! And this is the agency you want to oversee MORE 'legal' immigration. Good applicants are tortured through our system for years. Our immigration system needs a giant enema.