In a battle between Missouri law and federal immigration laws, Missouri courts have ruled in favor of Missouri law.
On Tuesday, April 2, 2013, the Missouri Court of Appeals for the Eastern District ruled in six cases that an applicant who uses forged documents – such as a social security card – in an effort to get employment in Missouri commits the crime of forgery. The lead case, State of Missouri v. Pablo Gilberto Diaz-Rey can be found here. Missouri statute 570.090 provides that it is a crime to use inauthentic writings or items as genuine with knowledge and an intent to defraud. The Missouri Court of Appeals declared that the use of knowingly false records to gain employment constitutes the crime of forgery.
You can expect this to be appealed to the Missouri Supreme Court and we will be watching.