What HR pros need to know about immigration and I-9s.

As an HR professional, you've been deputized to enforce the nation's immigration laws. Before a newly hired employee begins work, employers must verify the worker is legally allowed to labor.

Within three business days, all new hires must complete Federal Form I-9, which guides the employment eligibility verification process. It lists permissible identity and work-eligibility documents. No documents, no work. Employer I-9 diligence is crucial to maintaining a workable immigration system.

But completing the I-9 form can be tricky. For example, employers must personally inspect the documents employees present and must assess whether they appear to be genuine and not altered or counterfeit.

Online resource Find detailed instructions on completing Form I-9, as well as the form itself, at tinyurl.com/I-9-instructions.

Laws governing immigration

The Immigration Reform and Control Act of 1986 requires employers to have each new employee complete an I-9 form documenting the employee's status to legally work in the United States--or to be "work authorized."

The U.S. Immigration and Nationality Act sets immigration rules, including what type of work permission various visa programs have.

Eligibility status

Here are some of the main immigration categories, their workauthorization status and the I-9 documentation that can demonstrate their status:

* U.S. citizen: All United States citizens are work authorized, subject to restrictions under child-labor laws and the like. Individuals become U.S. citizens through birth in the United States or its territories, through their parental citizenship status or through naturalization. To prove citizenship, individuals can provide a copy of a certificate of their birth within the United States or its territories or a U.S. passport. Naturalized citizens can provide a copy of their naturalization certificates or a U.S. passport.

* Green card holder: Individual noncitizens who have been granted permanent immigration status receive what's commonly called a green card. It's officially known as a Permanent Resident Card. It comes with the same right to work as a citizen has, with some limited national-security exceptions.

* Permanent immigrant workers:

Individuals who want to immigrate to the U.S. and remain indefinitely may apply for one of several employment-based visas.

* Temporary nonimmigrant workers:

These individuals are not immigrants. Once their visas expire, they must leave the U.S.

* Deferred Action for...