Being called for a fraud interview that's not part of the usual application process is definitely not a good sign. It means that your application has been singled out because you haven't given enough evidence to prove a real marriage, your application contains some inconsistencies, or something about you and your spouse looks suspicious. But if your marriage really is authentic, you shouldn't be worried. The interview is your opportunity to show USCIS that you married because you wanted to, and not just to get a green card.

Marriage fraud interviews will occur even after the I-130 is approved. Almost always, if you are "adjusting status" (applying for your green card without going back to your home country to get a visa), USCIS will call you and your spouse in for an interview. Although the purpose of this interview is not just to uncover fraud, the USCIS officer will be questioning you and your spouse and looking for any signs that your marriage is not real.

The same thing will happen if you're outside the U.S. at a U.S. consulate applying for an immigrant visa based on your marriage (although your spouse probably won't be able to attend this interview with you).  The visa officer will want to hear you give a realistic account of the development of your relationship. The officer will also try to spot any inconsistencies between your story and the application forms and documents.

If you have not reached your second wedding anniversary by the time you are approved for a green card or enter the U.S. on an immigrant visa, you will receive what's called conditional residency, which lasts for two years. A fraud interview can be scheduled during or at the expiration of that time, as well.

If after an initial interview USCIS still has suspicions, and you're in the U.S., it will summon you and your spouse for a second, more intense and probing interview, known as a "Stokes" interview. This might be the time to start worrying.

If you get notice of a second (Stokes) interview, consider hiring a lawyer to attend the interview with you. The lawyer does not really have a lot of power over the questions that you are required to answer, but can be a calming influence on everyone. Also, if the lawyer attends the interview, he or she will be better prepared to deal with any follow-up matters.

Once you or your spouse gets to a fraud interview, you will have to meet with an officer whose main job is try to detect wrongdoers, not grant visas or green cards. The interviewer will not be trying to make you feel comfortable. His or her job is to push a person with questions until the person trips himself up, confesses to marriage fraud, or finally convinces the interviewer that the marriage is real.  But if the officer asks you a question you feel is too personal and inappropriate, do not answer it. You can tell the officer that you think the question is inappropriate and ask to speak to a supervisor about it.

Usually, straightforward, hard questioning is enough. Couples perpetrating a fraudulent marriage can do all the homework in the world, but when one of them forgets or does not know the answer to an obvious question—like where they went right after their wedding—that applicant often crumbles and confesses.

Occasionally, a hard-nosed USCIS officer will engage in harsher tactics, such as falsely telling someone that their spouse has already confessed that the marriage is bogus, in order to push the interviewee into confessing. Or, the officer may use flat-out intimidation, reminding the interviewee about the jail time and money fines a person faces if caught committing marriage fraud.

Sensing that the interviewee is feeling low, the officer may ask him or her to sign something withdrawing the visa petition or stating that the marriage is a fraud. If your marriage really is an honest one, do not agree to or sign anything. Ask to stop the interview and to reschedule with a lawyer present.