delivered the opinion of the Court.
This case presents only one question: whether conspiracy to defraud the United States of taxes on distilled *224spirits is a “crime involving moral turpitude” within the meaning of § 19 (a) of the Immigration Act of 1917.1
Respondent, a native and citizen of Italy, has lived continuously in the United States since he entered this country in 1921.2 In 1937, respondent was indicted under 18 U. S. C. § 883 for conspiring with seven other defendants to violate twelve sections of the Internal Revenue Code. The indictment specifically charged him with possessing whiskey and alcohol “with intent to sell it in fraud of law and evade the tax thereon.” He was further accused of removing and concealing liquor “with intent to defraud the United States of the tax thereon.” 4 After pleading guilty, respondent was sentenced to imprisonment in a federal penitentiary for a term of one year and one day.
Respondent served his sentence under this conviction, and was released from custody. Less than a year later, he returned to his former activities and in December 1939, he was indicted again with eight other defendants for violating the same federal statutes. He was charged with conspiring to “unlawfully, knowingly, and willfully *225defraud the United States of tax on distilled spirits.”5 After being tried and found guilty in 1941, he was sentenced to imprisonment for two years.
While serving his sentence under this second conviction, deportation proceedings were commenced against the respondent under § 19 (a) of the Immigration Act which provides:
. . any alien . . . who is hereafter sentenced more than once to such a term of imprisonment [one year or more] because of conviction in this country of any crime involving moral turpitude, committed at any time after entry . . . shall, upon the warrant of the Attornéy General, be taken into custody and deported. ...”6
After continued hearings and consideration of the case by the Commissioner of Immigration and Naturalization and by the Board of Immigration Appeals, respondent was ordered to be deported in January 1946, on the ground that he had twice been convicted and sentenced to terms of one year or more of crimes involving moral turpitude.7 Deportation was deferred from time to time *226at respondent’s request until 1949, when the District Director of Immigration and Naturalization moved to execute the warrant of deportation.
Respondent then sought habeas corpus in the District Court, claiming that the deportation order was invalid because the crimes of which he had been convicted did not involve moral turpitude. The District Court held a hearing, and dismissed the petition. The Court of Appeals reversed the order of the District Court and ordered that the respondent be discharged. 183 F. 2d 768 (1950). The Court of Appeals stated that “crimes involving moral turpitude,” as those words were used in the Immigration Act, “were intended to include only crimes of violence, or crimes which are commonly thought of as involving baseness, vileness or depravity. Such a classification does not include the crime of evading the payment of tax on liquor, nor of conspiring to evade that tax.” 183 F. 2d at 772. We granted certiorari to review the decision, 340 U. S. 890 (1950), as conflicting with decisions of the courts of appeals in other circuits.
This Court has interpreted the provision of the statute before us “to authorize deportation only where an alien having committed a crime involving moral turpitude and having been convicted and sentenced, once again commits a crime of that nature and is convicted and sentenced for it.” Fong Haw Tan v. Phelan, 333 U. S. 6, 9-10 (1948). Respondent has on two separate occasions been convicted of the same crime, conspiracy to defraud the United States of taxes on distilled spirits. Therefore, our inquiry in this case is narrowed to determining whether this particular offense involves moral turpitude. Whether *227or not certain other offenses involve moral turpitude is irrelevant and beside the point.
The term “moral turpitude” has deep roots in the law. The presence of moral turpitude has been used as a test in a variety of situations, including legislation governing the disbarment of attorneys8 and the revocation of medical licenses.9 Moral turpitude also has found judicial employment as a criterion in disqualifying and impeaching witnesses,10 in determining the measure of contribution between joint tort-feasors,11 and in deciding whether certain language is slanderous.12
In deciding the case before the Court, we look to the manner in which the term “moral turpitude” has been applied by judicial decision. Without exception, federal and state courts have held that a crime in which fraud is an ingredient involves moral turpitude. In the construction of the specific section of the Statute before us, a court of appeals has stated that fraud has ordinarily been the test to determine whether crimes not of the gravest character involve moral turpitude. United States ex rel. Berlandi v. Reimer, 113 F. 2d 429 (1940).
In every deportation case where fraud has been proved, federal courts have held that the crime in issue involved moral turpitude. This has been true in a variety of situ*228ations involving fraudulent conduct: obtaining goods under fraudulent pretenses, Bermann v. Reimer, 123 F. 2d 331 (1941); conspiracy to defraud by deceit and falsehood, Mercer v. Lence, 96 F. 2d 122 (1938); forgery with intent to defraud, United States ex rel. Popoff v. Reimer, 79 F. 2d 513 (1935); using the mails to defraud, Ponzi v. Ward, 7 F. Supp. 736 (1934); execution of chattel mortgage with intent to defraud, United States ex rel. Millard v. Tuttle, 46 F. 2d 342 (1930); concealing assets in bankruptcy, United States ex rel. Medich v. Burmaster, 24 F. 2d 57 (1928); issuing checks with intent to defraud, United States ex rel. Portada v. Day, 16 F. 2d 328 (1926). In the state courts, crimes involving fraud have universally been held to involve moral turpitude.13
Moreover, there have been two other decisions by courts of appeals prior to the decision now under review on the question of whether the particular offense before us in this case involves moral turpitude within the meaning of § 19 (a) of the Immigration Act. In United States ex rel. Berlandi v. Reimer, 113 F. 2d 429 (1940), and Maita v. Haff, 116 F. 2d 337 (1940), courts of appeals specifically decided that the crime of conspiracy to violate the internal revenue laws by possessing and concealing distilled spirits with intent to defraud the United States of taxes involves moral turpitude. Furthermore, in Guarneri v. Kessler, 98 *229F. 2d 580 (1938), a court of appeals held that the crime of smuggling alcohol into the United States with intent to defraud the United States involves moral turpitude.
In view of these decisions, it can be concluded that fraud has consistently been regarded as such a contaminating component in any crime that American courts have, without exception, included such crimes within the scope of moral turpitude. It is therefore clear, under an unbroken course of judicial decisions, that the crime of conspiring to defraud the United States is a “crime involving moral turpitude.”
But it has been suggested that the phrase “crime involving moral turpitude” lacks sufficiently definite standards to justify this deportation proceeding and that the statute before us is therefore unconstitutional for vagueness. Under this view, no crime, however grave, could be regarded as falling within the meaning of the term “moral turpitude.” The question of vagueness was not raised by the parties nor argued before this Court.
It is significant that the phrase has been part of the immigration laws for more than sixty years.14 As dis*230cussed above, the phrase “crime involving moral turpitude” has also been used for many years as a criterion in a variety of other statutes. No case has been decided holding that the phrase is vague, nor are we able to find any trace of judicial expression which hints that the phrase is so meaningless as to be a deprivation of due process.
Furthermore, this Court has itself construed the phrase “crime involving moral turpitude.” In United States ex rel. Volpe v. Smith, Director of Immigration, 289 U. S. 422 (1933), the Court interpreted the same section of the Immigration Statute now before us. There, an alien had been convicted of counterfeiting government obligations with intent to defraud, and one question of the case was whether the crime of counterfeiting involved moral turpitude. This question was raised by the parties and discussed in the briefs. The Court treated the question without hesitation, stating that the crime of counterfeiting obligations of the United States was “plainly a crime involving moral turpitude.” 289 U. S. at 423. (Emphasis supplied.)
The essential purpose of the “void for vagueness” doctrine is to warn individuals of the criminal consequences of their conduct. Williams v. United States, 341 U. S. 97, decided April 23, 1951; Screws v. United States, 325 U. S. 91, 103-104 (1945). This Court has repeatedly stated that criminal statutes which fail to give due notice that an act has been made criminal before it is done are unconstitutional deprivations of due process of law. Lanzetta v. New Jersey, 306 U. S. 451 (1939); United States v. Cohen Grocery Co., 255 U. S. 81 (1921). It should be emphasized that this statute does not declare certain conduct to be criminal. Its function is to apprise aliens of the consequences which follow after conviction and sentence of the requisite two crimes.
*231Despite the fact that this is not a criminal statute, we shall nevertheless examine the application of the vagueness doctrine to this case. We do this in view of the grave nature of deportation. The Court has stated that “deportation is a drastic measure and at times the equivalent of banishment or exile .... It is the forfeiture for misconduct of a residence in this country. Such a forfeiture is a penalty.” Fong Haw Tan v. Phelan, supra, at 10. We shall, therefore, test this statute under the established criteria of the “void for vagueness” doctrine.
We have several times held that difficulty in determining whether certain marginal offenses are within the meaning of the language under attack as vague does not automatically render a statute unconstitutional for indefiniteness. United States v. Wurzbach, 280 U. S. 396, 399 (1930). Impossible standards of specificity are not required.15 United States v. Petrillo, 332 U. S. 1 (1947). The test is whether the language conveys sufficiently definite warning as to the proscribed conduct when measured *232by common understanding and practices. Connally v. General Construction Co., 269 U. S. 385 (1926).
We conclude that this test has been satisfied here. Whatever else the phrase “crime involving moral turpitude” may mean in peripheral cases, the decided cases make it plain that crimes in which fraud was an ingredient have always been regarded as involving moral turpitude. We have recently stated that doubt as to the adequacy of a standard in less obvious cases does not render that standard unconstitutional for vagueness. See Williams v. United States, supra. But there is no such doubt present in this case. Fraud is the touchstone by which this case should be judged. The phrase “crime involving moral turpitude” has without exception been construed to embrace fraudulent conduct. We therefore decide that Congress sufficiently forewarned respondent that the statutory consequence of twice conspiring to defraud the United States is deportation.
Reversed.
39 Stat. 889, as amended, 8 U. S. C. § 155 (a).
Less than three years after entering the United States, respondent was convicted for transporting liquor and sentenced to a term in the reformatory. In 1931, he was convicted and fined for transferring license plates.
35 Stat. 1096, now 18 U. S. C. § 371:
“If two or more persons conspire either to commit any offense against the United States, or to defraud the United States in any manner or for any purpose, and one or more of such parties do any act to effect the object of the conspiracy, each of the parties to such conspiracy shall be fined not more than $10,000, or imprisoned not more than two years, or both.”
These charges were based upon 26 U. S. C. (1934 ed.) §§ 1155 (f), 1440 and 1441.
The record establishes that respondent was a large-scale violator engaged in a sizable business. The second indictment alone charged him with possessing 4,675 gallons of alcohol and an undetermined quantity of distilled spirits. At the rate of $2.25 a gallon then in effect, the tax on the alcohol alone would have been over $10,000.
39 Stat. 889, as amended, 8 U. S. C. § 155 (a).
Section 19(a) further provides: . . The provision of this section respecting the deportation of aliens convicted of a crime involving moral turpitude shall not apply to one who has been pardoned, nor shall such deportation be made or directed if the court, or judge thereof, sentencing such alien for such crime shall, at the time of imposing judgment or passing sentence or within thirty days thereafter, due notice having first been given to representatives of the State, make a recommendation to the Attorney General that such alien shall not be deported in pursuance of this chapter . . . .” 39 *226Stat. 889, as amended, 8 U. S. C. § 155 (a). The record does not indicate that respondent has been pardoned, nor that the sentencing judge recommended that he not be deported, nor that respondent requested that such recommendation be made.
In re Kirby, 10 S. D. 322, 73 N. W. 92, 39 L. R. A. 856 (1897). Bartos v. United States District Court, 19 F. 2d 722 (1927); see Bradway, Moral Turpitude as the Criterion of Offenses that Justify Disbarment, 24 Cal. L. Rev. 9-27.
Fort v. Brinkley, 87 Ark. 400, 404, 112 S. W. 1084, 1085 (1908). “It seems clearly dedueible from the above cited authorities that the words ‘moral turpitude’ had a positive and fixed meaning at common law . . . .”
3 Wigmore, Evidence (3d ed.), 540; cases are collected at 40 A. L. R. 1049, and 71 A. L. R. 219.
Fidelity & Cas. Co. v. Christenson, 183 Minn. 182, 236 N. W. 618 (1931).
Baxter v. Mohr, 37 Misc. 833, 76 N. Y. S. 982 (1902).
State decisions have held that the following crimes involve moral turpitude: passing a check with intent to defraud, Bancroft v. Board of Governors of Registered Dentists of Oklahoma, 202 Okla. 108, 210 P. 2d 666 (1949); using the mails to defraud, Neibling v. Terry, 352 Mo. 396, 177 S. W. 2d 502 (1944), In re Comyns, 132 Wash. 391, 232 P. 269 (1925); obtaining money and property by false and fraudulent pretenses, In re Needham, 364 Ill. 65, 4 N. E. 2d 19 (1936); possessing counterfeit money with intent to defraud, Fort v. Brinkley, 87 Ark. 400, 112 S. W. 1084 (1908). One state court has specifically held that the wilful evasion of federal income taxes constitutes moral turpitude. Louisiana State Bar Assn. v. Steiner, 204 La. 1073, 16 So. 2d 843 (1944).
The term “moral turpitude” first appeared in the Act of March 3, 1891, 26 Stat. 1084, which directed the exclusion of “persons who have been convicted of a felony or other infamous crime or misdemeanor involving moral turpitude.” Similar language was reenacted in the Statutes of 1903 and 1907. § 2, Act of March 3, 1903, 32 Stat. 1213; § 2, Act of Feb. 20, 1907, 34 Stat. 898. It has been suggested that the fact that this phrase has been used in the Immigration Laws for over sixty years has no weight in upholding its constitutionality. Of course, the mere existence of a statute for over sixty years does not provide immunity from constitutional attack. We have recently held an equally ancient statute unconstitutional for vagueness. Winters v. New York, 333 U. S. 507 (1948). There, a statute, which employed vague terminology wholly lacking in common law background or interpretation, was aimed at limiting rights of free speech. Even in the Winters case, however, several dissenting members of this Court were of the view that the venerability of the statute was an element to be considered in deciding the question of vagueness.
The phrase “crime involving moral turpitude” presents no greater uncertainty or difficulty than language found in many other statutes repeatedly sanctioned by the Court. The Sherman Act provides the most obvious example, “restraint of trade” as construed to mean “unreasonable or undue restraint of trade,” Nash v. United States, 229 U. S. 373 (1913). Compare other statutory language which has survived attack under the vagueness doctrine in this Court: “in excess of the number of employees needed by such licensee to perform actual services,” United States v. Petrillo, 332 U. S. 1 (1947); “any offensive, derisive or annoying word,” Chaplinsky v. New Hampshire, 315 U. S. 568 (1942); “connected with or related to the national defense,” Gorin v. United States, 312 U. S. 19 (1941); “psychopathic personality,” Minnesota v. Probate Court, 309 U. S. 270 (1940); “wilfully overvalues any security,” Kay v. United States, 303 U. S. 1 (1938); “fair and open competition,” Old Dearborn Co. v. Seagram Corp., 299 U. S. 183 (1936); “reasonable variations shall be permitted,” United States v. Shreveport Grain & Elevator Co., 287 U. S. 77 (1932); “unreasonable waste of natural gas,” Bandini Petro*232leum Co. v. Superior Court, 284 U. S. 8 (1931); “political purposes," United States v. Wurzbach, 280 U. S. 396 (1930); “range usually occupied by any cattle grower,” Omaechevarria v. Idaho, 246 U. S. 343 (1918).