285.530.  Employment of unauthorized aliens prohibited — federal work authorization program, requirements for participation in — liability of contractors and subcontractors. — 1.  No business entity or employer shall knowingly employ, hire for employment, or continue to employ an unauthorized alien to perform work within the state of Missouri.

  2.  As a condition for the award of any contract or grant in excess of five thousand dollars by the state or by any political subdivision of the state to a business entity, or for any business entity receiving a state-administered or subsidized tax credit, tax abatement, or loan from the state, the business entity shall, by sworn affidavit and provision of documentation, affirm its enrollment and participation in a federal work authorization program with respect to the employees working in connection with the contracted services.  Every such business entity shall also sign an affidavit affirming that it does not knowingly employ any person who is an unauthorized alien in connection with the contracted services.  Any entity contracting with the state or any political subdivision of the state shall only be required to provide the affidavits required in this subsection to the state and any political subdivision of the state with which it contracts, on an annual basis.  During or immediately after an emergency, the requirements of this subsection that a business entity enroll and participate in a federal work authorization program shall be suspended for fifteen working days.  As used in this subsection, "emergency" includes the following natural and manmade disasters:  major snow and ice storms, floods, tornadoes, severe weather, earthquakes, hazardous material incidents, nuclear power plant accidents, other radiological hazards, and major mechanical failures of a public utility facility.

  3.  All public employers shall enroll and actively participate in a federal work authorization program.

  4.  An employer may enroll and participate in a federal work authorization program and shall verify the employment eligibility of every employee in the employer's hire whose employment commences after the employer enrolls in a federal work authorization program.  The employer shall retain a copy of the dated verification report received from the federal government.  Any business entity that participates in such program shall have an affirmative defense that such business entity has not violated subsection 1 of this section.

  5.  A general contractor or subcontractor of any tier shall not be liable under sections 285.525 to 285.550 when such general contractor or subcontractor contracts with its direct subcontractor who violates subsection 1 of this section, if the contract binding the contractor and subcontractor affirmatively states that the direct subcontractor is not knowingly in violation of subsection 1 of this section and shall not henceforth be in such violation and the contractor or subcontractor receives a sworn affidavit under the penalty of perjury attesting to the fact that the direct subcontractor's employees are lawfully present in the United States.