At age 22, Nguyen pleaded guilty to sexual assault; this made him subject to deportation based on his criminal record.

[10] A concurring opinion by Associate Justices Antonin Scalia and Clarence Thomas proposed that the Supreme Court simply did not have the power of "conferral of citizenship on a basis other than that prescribed by Congress".

[11] The dissent (written by Associate Justice Sandra Day O'Connor) concluded that the INS "[had] not shown an exceedingly persuasive justification for the sex-based classification... because it [had] failed to establish at least that the classification substantially relate[d] to the achievement of important government objectives", and on that basis the minority would have ruled in Nguyen's favor.

[13] After the Supreme Court decision, the INS attempted to deport Nguyen, but was unsuccessful because of a Vietnamese government policy barring the repatriation of convicts from the United States.

[14][15] Nguyen and his father sought to reopen the deportation proceedings, and when this effort was unsuccessful, appealed to the courts again, claiming that the refusal by the Board of Immigration Appeals to reopen Nguyen's case deprived him of due process of law and denied the father's right to enjoy his son's companionship.