[VladRussian2]

as far as i heard, Immigration, before issuing the marriage-based Green Card, may grill very seriously (various pretty intimate details, etc...) trying to determine whether the marriage is real. Don't think that IRS would do less when it comes to (multi)millions.

For example: http://marriage-and-immigrationlaw.blogspot.com/2007/09/must...

[Pinckney]

Entering into a marriage to evade immigration laws specifically made a felony by statute. (8 U.S.C. § 1325).

http://www.law.cornell.edu/uscode/text/8/1325