Dear Customer (name blocked for privacy),

It would be hard to prove, after 10 years of marriage, that the marriage was not in good faith. Many marriages between citizens only last a year or two, even when they were entered into with good faith.

Once a person becomes a citizen, they can only lose citizenship through any of the following voluntary acts WITH THE INTENTION of giving up citizenship.

1) obtaining naturalization in a foreign state (Sec. 349 (a) (1) INA);

(2) taking an oath, affirmation or other formal declaration to a foreign state or its political subdivisions (Sec. 349 (a) (2) INA);

(3) entering or serving in the armed forces of a foreign state engaged in hostilities against the U.S. or serving as a commissioned or non-commissioned officer in the armed forces of a foreign state (Sec. 349 (a) (3) INA);

(4) accepting employment with a foreign government if (a) one has the nationality of that foreign state or (b) a declaration of allegiance is required in accepting the position (Sec. 349 (a) (4) INA);

(5) formally renouncing U.S. citizenship before a U.S. consular officer outside the United States (sec. 349 (a) (5) INA);

(6) formally renouncing U.S. citizenship within the U.S. (but only "in time of war") (Sec. 349 (a) (6) INA);

(7) conviction for an act of treason (Sec. 349 (a) (7) INA).

The time to prove bad faith is during the first two years of marriage, before the conditions are removed from the temporary green card. Still, even then, it is not absolute.

Even with proof, he would still be a citizen. Under any circumstances, people change their minds. It only takes 5 years of green card status to apply for citizenship, so 10 years, in the immigration court mindset, will be seen as good faith, no matter what evidence exists for his intentions at the time of marriage.

Because he is a citizen, you need one of the reasons listed above in order to cause his citizenship to be withdrawn.