U.S. citizens are required to carry a passport when traveling internationally by air. A passport card is sufficient when traveling by land or sea within the designated region of the Western Hemisphere Travel Initiative. Both passport cards and full passports require a background check that prevents some citizens from obtaining them.

Citizenship and Identity

When you apply for a passport, you must prove your citizenship and identity. The documents you submit, such as a previously issued passport, a certified birth certificate, or a naturalization certificate, are checked for authenticity. People who are not U.S. citizens, whether by birth or naturalization, are not eligible for a U.S. passport. The State Department provides numerous options for those who do not have primary proof of citizenship or identity.

Drug Trafficking

If you have been convicted of certain drug offenses, you might be ineligible for a passport. Violations of federal or state drug laws, whether misdemeanors or felonies, can result in denial of a passport if the crime involved crossing an international border. A first conviction for possession is excluded from this penalty. This is a complex area of the law, and much depends on your individual circumstances. Consult an attorney before applying for a passport if you have previous drug convictions that involved international borders.

Current Criminal Matters

Local, state and federal law enforcement agencies sometimes place restrictions on passport issuance for people involved in current criminal matters. If you have an outstanding arrest warrant, are on parole or probation with the condition that you not leave the U.S., are facing extradition, or are under subpoena or court order, you might be ineligible for a passport. Speak with your attorney if you are involved in any criminal proceedings or court orders.

Issues Involving Minors

If you owe back child support, you might not be able to obtain a passport. As of 2013, those who owe $2,500 or more are placed on a list with the U.S. Department of Health and Human Services. The State Department routinely checks this list before issuing a passport. You must work with your state agency to pay off the debt and remove your name from the list. (See Reference 5)