Very doubtful indeed.
May theoretically be within a state's right, but would immediately lead to lawsuits and probable overturning of the law.
There is also the quite tricky issue of deciding what is meant by "on welfare."
Well if it was them, they'd do it anyway and make the other side take action. Then, they'd ignore the results of any court-mandated action. Then, they'd choose to not enforce any law that would impede them.
Why don't we do that too? We're simply allowing the enemy [and they are an enemy] to defeat us by having us enforce rules on ourselves that they do NOT adhere to. Alinksy #4?
Based on what the guy posted to me, there’s been a lot of research into the issue. Sorry I don’t have the links (and too lazy to undertake a search right now)!