Is this tax fraud?

An acquaintance of mine contracts for a US based company and receives his paycheques in his wife's name. His wife is in a completely different profession than his, so there's no way she can do the work he's doing. He says because its a contracting position and his employer is writing paycheques in his wife's name, its completely legal and not tax fraud. Is it?

Edit: Asking the question because I want to educate him to not do this and pay the proper tax amount before he files his returns this year(if it turns out that it is actually tax fraud)