If you want to become a citizen of the United States, you have to answer a lot of questions, some of which are very broad and many of which seek potentially embarrassing information. In a case the Supreme Court heard yesterday, the U.S. government takes the position that a false answer to any of those questions, no matter how trivial or irrelevant the subject, is enough to strip you of your citizenship years after you were naturalized. That argument encountered a lot of resistance from the Court and prompted a startling confession from Chief Justice John Roberts.

"Some time ago," Roberts told Assistant to the Solicitor General Robert Parker, "outside the statute of limitations, I drove 60 miles an hour in a 55-mile-an-hour zone….I was not arrested." Had Roberts done that as a green-card holder seeking citizenship, he would have been obligated to check the "yes" box next to Question 22 in Part 12 of his application for naturalization: "Have you EVER committed, assisted in committing, or attempted to commit a crime or offense for which you were NOT arrested?" According to the government, checking the "no" box could have life-altering consequences. "You say that if I answer that question no," Roberts said, "20 years after I was naturalized as a citizen, you can knock on my door and say, 'Guess what, you're not an American citizen after all.'" Parker confirmed that was indeed what he was saying. "Oh, come on," the chief justice replied.

At the center of the case, Maslenjak v. United States, is the meaning of 18 USC 1425, which makes it a felony to "procure" citizenship "contrary to law." In addition to a prison term of up to 25 years, a conviction under that statute triggers automatic loss of citizenship. Divna Maslenjak, an ethnic Serb from Bosnia who became a citizen in 2007, was convicted of violating 18 USC 1425 because she lied about her husband's military service while seeking refugee status in 1998 and did not acknowledge the lie when she applied for citizenship. It is a matter of dispute whether that lie, which violated another law making it a crime for a naturalization applicant to knowingly make a false statement under oath, actually helped Maslenjak become a citizen. But during her trial the prosecution argued that it did not matter. The judge agreed, telling jurors they could convict Maslenjak of illegally procuring citizenship "even if you find that a false statement did not influence the decision to approve the defendant's naturalization."

Last year the U.S. Court of Appeals for the 6th Circuit approved that interpretation of the law, parting company with four other federal appeals courts. Yesterday Parker urged the Supreme Court to uphold the 6th Circuit's decision. "What Congress was concerned here with is not what people lied about," he said. "Rather, it was the fact that they lied." Several justices seemed skeptical. "How can an immaterial statement procure naturalization?" asked Ruth Bader Ginsburg. Elena Kagan said it "seems quite natural" to require some causal connection between the false statement and obtaining citizenship. Samuel Alito suggested it was rather odd to say that someone "procured X contrary to law, but the thing that she did had no potential to help her get that thing."

Several justices also were dismayed by the sweeping implications of the government's position. Stephen Breyer said it is "rather surprising that the government of the United States thinks that Congress is interpreting this statute and wanted it interpreted in a way that would throw into doubt the citizenship of vast percentages of all naturalized citizens." Noting that the questions posed to would-be citizens "are unbelievably broad," Breyer added his own hypothetical to Roberts' speeding example: "I walked into the immigration hearing with a pocketknife in a government building, a Boy Scout knife I carry on my key chain….No one ever saw it. It was there the whole time, and then I walked out."

That offense likewise would require a "yes" to Question 22, and a "no" would be grounds for denaturalization. So would the failure to submit a complete list of current and past "nicknames," no matter how unflattering, as Justice Sonia Sotomayor noted. Not to be outdone, Parker offered his own example: "You could, you know, lie about your weight, let's say. You're embarrassed that you weigh 170 pounds, and so you claim that you weigh 150." That lie also could cost you your citizenship, according to the government's reading of the law. Congress "has specifically provided that it is a crime to lie under oath in the naturalization process, even about an immaterial matter," Parker said, "and it has provided that certain of those immaterial lies are categorical bars to naturalization."

In light of that interpretation, ponder the minefield that is Part 12, Question 9: "Have you EVER been a member of, involved in, or in any way associated with, any organization, association, fund, foundation, party, club, society, or similar group in the United States or in any other location in the world?" The form then asks for the name and purpose of any such groups, along with the applicant's membership dates and "any evidence to support your answers." As the Immigrant Defense Project notes in a brief opposing the government's position, there are innocent reasons why an applicant might fail to answer that question completely and accurately:

The scope of the question is breathtaking; it contains three catch-all clause ("in any way associated with," "or similar group," and "in any other location in the world"), and asks for information spanning the applicant's entire life. No definition of the means of participation (member, involvement, organization) or the associations themselves (organization, association, fund, foundation, party, club, society, or similar group) are included, making the potential list near infinite. It is not clear whether the question seeks information about charitable donations, grade school clubs, intramural sports teams, tenant associations, and other seemingly trivial involvement or groups. If an applicant were to omit associations under the assumption that they were too trivial, irrelevant, fleeting, or minor to rise to the significance of the application, the applicant's liberty and citizenship would be threatened by the immense prosecutorial power the government seeks. Similarly, if an applicant were to leave out information about participation in a group committed to the peaceful advancement of certain populations or viewpoints considered deeply controversial (reproductive freedoms, LGBTQ rights, etc.), the omissions could be reached by the government's claimed prosecutorial power.

During oral argument, Roberts emphasized the threat posed by that power. "It is certainly a problem of prosecutorial abuse," he said. "If you take the position that…not answering about the speeding ticket or the nickname is enough to subject that person to denaturalization, the government will have the opportunity to denaturalize anyone they want, because everybody is going to have a situation where they didn't put in something like that—or at least most people….That to me is troublesome to give that extraordinary power—which, essentially, is unlimited power, at least in most cases—to the government."