In the 1950 U.S. Supreme Court case Jordan, District Director of Immigration & Naturalization v. De George, the court ruled in favor of Mr. De George, an Italian immigrant who had been convicted twice for fraudulent evasion of liquor taxes and was facing deportation as a result. The Immigration and Nationality Act stated that any alien convicted of two crimes involving "moral turpitude" could be deported; however, it did not clearly define what constituted moral turpitude. The Supreme Court held that despite this lack of definition within the statute itself, fraud has consistently been recognized by courts to involve moral turpitude and thus falls under its purview. However, due to concerns about vagueness violating Due Process rights under the Fifth Amendment - specifically regarding fair warning - they also determined that only those offenses which are clearly understood to involve moral turpitude can justify deportation on these grounds.

In the dissenting opinion for Jordan v. De George, Justice Jackson argued that the term "moral turpitude" was too vague to be used as a basis for deportation. He pointed out that even legal professionals and judges could not agree on what constituted moral turpitude, making it unfair to expect immigrants with limited English proficiency and knowledge of U.S. law to understand this concept. Furthermore, he noted that there were no clear guidelines or standards in place regarding which crimes involved moral turpitude and which did not; decisions seemed arbitrary rather than based on consistent principles or rules. Therefore, using such an ambiguous term violated due process rights by failing to provide adequate notice of what behavior could lead to deportation.