View source for Mann Act

==Legal application==
Although the law was created to stop forced [[sexual slavery]] of women, the most common initial use of the Mann Act was to prosecute men for having sex with underage females.<ref name="Elizabeth Faue 1923"/> The phrase "immoral purpose" in the statute allowed a broad application of the law following its affirmation in {{cite court | litigants=Caminetti v. United States | vol=242 | reporter=U.S. | opinion=470 | date=1917 | url=https://caselaw.findlaw.com/us-supreme-court/242/470.html | quote=The authority of Congress to keep the channels of interstate commerce free from immoral and injurious uses has been frequently sustained, and is no longer open to question. | postscript=none}}

In addition to its stated purpose of preventing human trafficking, the law was used to prosecute unlawful premarital, extramarital, and interracial relationships. The penalties would be applied to men whether or not the woman involved consented, and if she had consented, the woman could be considered an accessory to the offense. Some attribute enactment of the law to the case of world-champion heavyweight boxer [[Jack Johnson]].<ref name="Reference A" /> Johnson was known to be intimate with white women, some of whom he met at the fighting venue after his fights. In 1912, he was prosecuted, and later convicted, for "transporting women across state lines for immoral purposes" as a result of his relationship with a white prostitute named Belle Schreiber;<ref name="Reference A" /> the month prior to the prosecution, Johnson had been charged with violating the Mann Act due to traveling with his white girlfriend, Lucille Cameron, who refused to cooperate with the prosecution and whom he married soon thereafter.<ref>{{cite news |title=Year in Cell for Johnson; $1,000 Fine, Too, for Pugilist's White Slavery Offense |url=https://www.nytimes.com/1913/06/05/archives/year-in-cell-for-johnson-1000-fine-too-for-pugilists-white-slavery.html|work=[[New York Times]] |date=June 4, 1913|access-date=March 14, 2018}}</ref>

The 1948 prosecution of Frank LaSalle for abducting [[Florence Sally Horner]] is believed to have been an inspiration for [[Vladimir Nabokov]] in writing his novel ''[[Lolita]]''.<ref>{{cite web |first=Alexander |last=Dolinin |url=http://www.libraries.psu.edu/nabokov/dolilol.htm |title=What Happened to Sally Horner?: A Real-Life Source of Nabokov's Lolita |publisher=Art & Humanities Library of [[Pennsylvania State University]] |location=State College, Pennsylvania |access-date=March 10, 2008 |archive-date=July 19, 2019 |archive-url=https://web.archive.org/web/20190719124016/https://www.libraries.psu.edu/nabokov/dolilol.htm |url-status=dead }}</ref> Humbert Humbert, the narrator, at one point explicitly refers to LaSalle. 

The Mann Act has also been used by the U.S. federal government to prosecute polygamists such as [[Mormon fundamentalism|Mormon fundamentalists]].<ref>{{cite book |last1=Langum |first1=David J |title=Crossing Over the Line: Legislating Morality and the Mann Act |date=1994 |publisher=University of Chicago Press |location=Chicago |isbn=978-0-226-46880-8 |page=211}}</ref><ref name="Red Emma Speaks 1972">{{cite book|first=Emma|last=Goldman|title=''Red Emma Speaks: Selected Writings and Speeches''|editor-first=Alix|editor-last=Kates Shulman |location=New York |publisher=[[Random House]] |date=1972|isbn=978-0-394-47095-5}}</ref> [[Morrill_Anti-Bigamy_Act|Bigamy is illegal in the U.S.]] and all states have [[Legality of polygamy in the United States|antipolygamy laws]]. [[Colorado City, Arizona]]; [[Hildale, Utah]]; [[Bountiful, British Columbia]], northern [[Mexico]] are historic locations of several Mormon sects that practiced polygamy,<ref name="mcneill">{{cite journal |first= Mary Ting |last= Lui Yi |title= Saving young girls from Chinatown: white slavery and woman suffrage, 1910–1920 |journal= Journal of the History of Sexuality |volume= 18 |issue= 3 |pages= 393–417 |date= September 1, 2009|doi= 10.1353/sex.0.0069 |jstor= 20542730|pmid= 19739340 |s2cid= 27886467 }}</ref> although [[The Church of Jesus Christ of Latter-day Saints]] has [[Second Manifesto|expressly forbidden]] polygamy since the start of the 20th century. Sect leaders and individuals have been charged under the Mann Act when "wives" are transported across the Utah–Arizona state line or the U.S.–Canadian and U.S.–Mexican borders.<ref name="archive.org"/>

===Notable prosecutions under the Mann Act===
{| class="wikitable sortable" style="margin-left:auto;margin-right:auto"
! scope=col| Person
! scope=col| Year
! scope=col| Decision
! scope=col class=unsortable|Notes
|-
|Bella Moore
|1910
|Convicted
|In ''People v. Moore''<ref>{{cite web| url=https://cite.case.law/nys/124/358/| title=People v. Moore| publisher=Caselaw Access Project| accessdate=December 8, 2025| archive-date=September 15, 2022| archive-url=https://web.archive.org/web/20220915142814/https://cite.case.law/nys/124/358/}}</ref>, an all-white jury convicted Bella Moore, a mixed race woman from New York, for the "compulsory prostitution" of two white women, Alice Milton and Belle Woods, using the Mann Act.<ref>{{Cite journal |last1=Donovan |first1=Brian |last2=Barnes-Brus |first2=Tori |date=2011 |title=Narratives of Sexual Consent and Coercion: Forced Prostitution Trials in Progressive-Era New York City |url=https://www.jstor.org/stable/23011884 |journal=Law & Social Inquiry |volume=36 |issue=3 |pages=597–619 |doi=10.1111/j.1747-4469.2011.01244.x |jstor=23011884 |s2cid=143108977 |issn=0897-6546|url-access=subscription }}</ref><ref>{{Cite book |last=Donovan |first=Brian |title=White slave crusades : race, gender, and anti-vice activism, 1887–1917 |date=2006 |isbn=978-0-252-09100-1 |location=Urbana |oclc=1154853069 |publisher=University of Illinois Press}}</ref>
|-
|| [[Jack Johnson]] ||1913||Convicted (pardoned in 2018)|| In October and November 1912, boxer Jack Johnson was arrested twice under the Mann Act. It was generally acknowledged that the arrests were racially motivated. A posthumous presidential pardon was granted in 2018 by President [[Donald Trump]].<ref>{{Cite news |last1=Eligon |first1=John |last2=Michael D. |first2=Shear |title=Trump Pardons Jack Johnson, Heavyweight Boxing Champion |url=https://www.nytimes.com/2018/05/24/sports/jack-johnson-pardon-trump.html |newspaper=The New York Times |access-date=May 24, 2018 |date=May 24, 2018}}</ref> 
|-
||[[Farley Drew Caminetti]] ||1913|| Convicted || Caminetti and Maury Diggs took their mistresses from [[Sacramento, California]] to [[Reno, Nevada]]. Their wives informed the police, and both men were arrested in Reno. ''[[Caminetti v. United States]]'' expanded Mann Act prosecutions from prostitution to non-commercial extramarital sex.<ref>{{cite news |title=Caminetti Guilty On Only One Count. Two Jurors Hold Out for Acquittal for Three Hours, but Finally Compromise |url=https://www.nytimes.com/1913/09/06/archives/caminetti-guilty-on-only-one-count-two-jurors-hold-out-for.html |quote=Farley Drew Caminetti, son of the Commissioner General of Immigration, was found guilty late to-day on one count of the indictment charging him with violation of the Mann White Slave act. |work=[[The New York Times]] |date=September 6, 1913 |access-date=August 20, 2010}}</ref>
|-
|| [[William I. Thomas]] ||1918||Acquitted ||Pioneering [[sociology|sociologist]] [[William I. Thomas]]'s academic career at the [[University of Chicago]] was irreversibly damaged after he was arrested under the Mann Act when caught in the company of Mrs. Granger, whose husband was an army officer with the [[American Expeditionary Forces|American forces]] in [[France]]. Thomas was acquitted at trial.<ref>{{cite news |title=Thomas and Woman Freed. Evidence Sought for Prosecution under the Mann Act |work=The New York Times |date=April 20, 1918 |url=https://www.nytimes.com/1918/04/20/archives/thomas-and-woman-freed-evidence-sought-for-prosecution-under-the.html |access-date=August 22, 2010}}</ref>
|-
|[[Fred Toney]]
|1918
|Convicted
|Toney, a professional [[baseball]] player, pleaded guilty to traveling with a woman, whom he falsely claimed was his wife, from [[Louisville, Kentucky]] to [[Cincinnati, Ohio]] where they lived together while he played for the [[Cincinnati Reds]]. He was sentenced to four months in jail.<ref>{{cite news |title=Fred Toney Pleads Guilty To White Slave Charge; Sentenced |url=https://www.newspapers.com/article/the-tennessean-fred-toney-pleads-guilty/128484417/ |access-date=19 July 2023 |work=[[The Tennessean]] |date=1 January 1919 |page=12}}</ref>
|-
|| [[Frank Lloyd Wright]] || 1926||Charges dropped || In October 1926, Wright and his future wife, [[Olga Lazovich Hinzenburg]] were accused of violating the Mann Act and he was arrested in [[Minnetonka, Minnesota]].<ref name=EricNPR />
|-
|| [[Finis Dake]] ||1937||Convicted||In 1937, he was convicted of violating the Mann Act by willfully transporting Emma Barelli, age 16, across the Wisconsin state line "for the purpose of debauchery and other immoral practices". The May 27, 1936, issue of the ''[[Chicago Daily Tribune]]'' reported that Dake registered at hotels in [[Waukegan, Illinois|Waukegan]], [[Bloomington, Illinois|Bloomington]], and [[East St. Louis, Illinois|East St. Louis]] with the girl under the name "Christian Anderson and wife". In order to avoid a jury trial and the possibility of being sentenced to a maximum of 10 years in prison and a fine of $10,000, Dake pleaded guilty. Subsequently, he served six months in the House of Corrections in [[Milwaukee, Wisconsin]].<ref>{{cite web |last=Chambers |first=Pastor Joseph |title=An Open Letter to Pastor Joseph Chambers, Author of an Article Entitled 'Confused Charismatic Theology & the Dake's Bible' |date=September 19, 1999 |place=Charlotte, NC |publisher=Paw Creek Ministries |url=http://www.dakebible.com/WebPages/joseph-chambers.htm |access-date=July 23, 2009 |website=dakebible.com}}</ref>
|-
||[[George Barker (poet)|George Barker]]||1940||Charges dropped||The [[UK|British]] poet was arrested crossing a state border with his lover [[Canadians|Canadian]] author [[Elizabeth Smart (Canadian author)|Elizabeth Smart]] in 1940. She described the arrest in her book ''[[By Grand Central Station I Sat Down and Wept]]''.
|-
|| [[Charlie Chaplin]] || 1944|| Acquitted ||Chaplin met [[Joan Barry (American actress)|Joan Barry]], age 24, in 1941. He signed her to a $75-a-week contract for a film he was putting together, and she became his mistress. By mid-1942, Chaplin let her contract expire. To send her home, Chaplin paid her train fare to New York which led to his arrest.<ref name=EricNPR/><ref>{{cite news |title=Mann & Woman |url=http://www.time.com/time/magazine/article/0,9171,850389,00.html |archive-url=https://web.archive.org/web/20080117060249/http://www.time.com/time/magazine/article/0,9171,850389,00.html |url-status=dead |archive-date=January 17, 2008 |magazine=[[Time (magazine)|Time]] |date=April 3, 1944|access-date=August 21, 2007}}</ref> Chaplin was acquitted of the charges.
|-
|| [[Rex Ingram (actor)|Rex Ingram]] ||1949||Convicted||Pleading guilty to the charge of transporting a teenage girl to New York for immoral purposes, the actor was sentenced to eighteen months in jail. He served just ten months of his sentence, but the incident had a serious impact on his career for the next six years.<ref>{{cite web |last=Eder |first=Bruce |title=Rex Ingram Biography |work=All Movie Guide |publisher=[[AMC (TV channel)|AMC]] |url=http://movies.amctv.com/person/216452/Rex-Ingram/details |access-date=July 23, 2009 |archive-date=July 27, 2011 |archive-url=https://web.archive.org/web/20110727232928/http://movies.amctv.com/person/216452/Rex-Ingram/details |url-status=dead }}</ref>
|-
||[[Frank La Salle]]||1950||Convicted|| La Salle was tried, convicted, and sentenced to 30 to 35 years in prison under the Mann Act for abducting and raping [[Florence Sally Horner]] during a 21-month period while traveling from New Jersey to California.{{citation needed|date=September 2018}}
|-
||[[Kid Cann]]||1959||Convicted/<br /> Acquitted on appeal||Cann, who was an [[organized crime]] figure from [[Minneapolis]], [[Minnesota]], was prosecuted and convicted for transporting a [[prostitute]] from [[Chicago]] to [[Minnesota]]. His conviction was later overturned on appeal. Cann was later prosecuted and convicted of offering a $25,000 [[jury tampering|bribe]] to a juror at his Mann Act trial.{{citation needed|date=June 2014}}
|-
|| [[Charles Manson]] ||1960||Charges dropped||Manson took two prostitutes from California to New Mexico to work.<ref>[[Vincent Bugliosi|Bugliosi, Vincent]] with [[Curt Gentry|Gentry, Curt]] (1994). ''Helter Skelter – The True Story of the Manson Murders 25th Anniversary Edition''. W. W. Norton & Company. {{ISBN|0-393-08700-X}}. pp. 137–146.</ref>
|-
|| [[Chuck Berry]] ||1962||Convicted||In January 1962, Berry was sentenced to three years in prison for offenses under the Mann Act when he had transported a girl, age 14, across state lines.<ref>{{cite web |title=Chuck Berry| work=Rock & Roll Hall of Fame | publisher=[[Rock and Roll Hall of Fame|The Rock and Roll Hall of Fame and Museum]] | url=https://www.rockhall.com/inductees/chuck-berry/bio}}</ref><ref name=EricNPR>{{cite web |last=Weiner |date=March 11, 2008 |first=Eric |title=The Long, Colorful History of the Mann Act |url=https://www.npr.org/templates/story/story.php?storyId=88104308 |work=All Things Considered |publisher=[[NPR]] |access-date=July 23, 2009}}</ref><ref>{{cite web|url=http://ftp.resource.org/courts.gov/c/F2/295/295.F2d.192.16752_1.html |title=295 F.2d 192 |publisher=ftp.resource.org |access-date=June 4, 2010 |url-status=dead |archive-url=https://web.archive.org/web/20101013023507/http://ftp.resource.org/courts.gov/c/F2/295/295.F2d.192.16752_1.html |archive-date=October 13, 2010}}</ref>
|-
|| [[Alamo Christian Foundation|Tony Alamo]]|| 2008 || Convicted||The former American religious leader was arrested under the Mann Act in September 2008.<ref>[http://edition.cnn.com/2008/CRIME/09/25/childporn.alamo/ Evangelist arrested, charged with child pornography crimes]. [[CNN]]. September 26, 2008. Retrieved July 30, 2011.</ref> He was subsequently convicted on 10 counts of interstate transportation of minors for illegal sexual purposes, rape, sexual assault, and contributing to the delinquency of minors.<ref>[https://archive.today/20120710224509/http://articles.cnn.com/2009-07-24/justice/arkansas.evangelist.trial_1_tony-alamo-christian-ministries-bernie-hoffman-arkansas Trial of Arkansas evangelist]. July 24, 2009. [[CNN]]. Retrieved July 30, 2011.</ref><ref>{{cite web|title=Evangelist Arrested In Child Sex Probe|url=https://www.cbsnews.com/news/evangelist-arrested-in-child-sex-probe/|publisher=CBS News|access-date=April 30, 2018|language=en|date=September 25, 2008}}</ref>
|-
|| [[Brian David Mitchell]] ||2010||Convicted ||Former street preacher and pedophile; convicted in 2010 of interstate kidnapping and unlawful transportation of a minor across state lines in connection with the 2002 abduction of [[Elizabeth Smart]]; currently serving a life sentence in federal prison.<ref>Enos, Robin (May 25, 2011), "[https://blogs.findlaw.com/blotter/2011/05/brian-david-mitchell--elizabeth-smart-abductor-gets-life-sentence.html Kidnapper Brian David Mitchell Sentenced to Life]. findlaw.com</ref>
|-
|| [[First Baptist Church (Hammond, Indiana)|Jack Schaap]] || 2012 ||Convicted || Pastor at mega-church [[First Baptist Church (Hammond, Indiana)|First Baptist Church]] and Chancellor of [[Hyles–Anderson College]], pleaded guilty to transportation of a minor, age 16, across state lines to have sex with her.<ref>{{cite news |url=http://www.huffingtonpost.com/2012/08/02/jack-schaap-confesses-to-_n_1732732.html |title=Jack Schaap Confesses To Sexual Relationship With Teen After Firing From Megachurch |work=[[The Huffington Post]] |date=August 2, 2012 |access-date=December 24, 2012}}</ref><ref>{{cite news |url=http://global.christianpost.com/news/jack-schaap-pleads-guilty-in-teen-sex-case-denies-knowing-act-was-crime-82304/ |title=Jack Schaap Pleads Guilty in Teen Sex Case, Denies Knowing Act Was Crime |newspaper=[[Christian Post]] |date=August 27, 2012 |access-date=December 24, 2012 |archive-url=https://web.archive.org/web/20130126192808/http://global.christianpost.com/news/jack-schaap-pleads-guilty-in-teen-sex-case-denies-knowing-act-was-crime-82304/ |archive-date=January 26, 2013 |url-status=dead}}</ref> He was sentenced to 12 years in prison.<ref>{{cite news |title=Judge Rejects Reduced Sentence In Former Pastor's Sex Case |url=http://chicago.cbslocal.com/2014/08/27/judge-rejects-reduced-sentence-in-former-pastors-sex-case/ |work=[[CBS Chicago]] |date=January 5, 2013 |access-date=April 8, 2015}}</ref>
|-
|| [[R. Kelly]] || 2021 ||Convicted || Singer/actor who has faced [[R. Kelly sexual abuse cases|multiple sexual abuse trials]]. At his first federal trial, he was charged with:<ref>{{multiref|
{{Cite Pacer|plaintiff=United States of America|defendant=Robert Sylvester Kelly|title=Jury Verdict|doc-number=238|date=September 27, 2021|pacer-number=434840|use-recap=yes|case-state=NY|case-district=ED|case-division=1|case-year=2019|case-type=cr|case-sequence=00286|access-date=2022-05-09}}|
{{Cite web|author=Lauren Aratani and Gloria Oladipo|date=2021-09-27|title=R Kelly found guilty on racketeering and sex trafficking charges|url=https://www.theguardian.com/music/2021/sep/27/r-kelly-racketeering-sex-trafficking|access-date=2021-09-27|website=[[The Guardian]]|language=en}}|
{{cite web |title=R. Kelly Trial Verdict: R. Kelly Is Found Guilty of All Counts and Faces Life in Prison |url=https://www.nytimes.com/live/2021/09/27/nyregion/r-kelly-trial-news#r-kelly-verdict-racketeering-sex-trafficking |website=The New York Times |access-date=25 June 2025 |date=September 27, 2021}}|
{{Cite web |date=2021-09-27 |title="R. Kelly" Convicted of All Counts by a Federal Jury in Brooklyn |url=https://www.justice.gov/usao-edny/pr/r-kelly-convicted-all-counts-federal-jury-brooklyn |access-date=2022-05-10 |website=www.justice.gov |language=en |archive-date=2022-08-08 |archive-url=https://web.archive.org/web/20220808131204/http://www.justice.gov/usao-edny/pr/r-kelly-convicted-all-counts-federal-jury-brooklyn |url-status=live }}
}}</ref>  
* one count of [[racketeering]] comprising 14 [[RICO predicate offenses|predicate acts]] against six females. Six of the acts were Mann Act offenses against four of the victims. He was found guilty of racketeering on the basis that 12 of the 14 acts were proved, including five Mann Act offenses against three of the victims. 
* eight Mann Act offenses against two of the victims, corresponding to four of the racketeering predicate acts; he was found guilty on all counts.
|-
|| [[Ghislaine Maxwell]] || 2021 ||Convicted ||Socialite/publishing heiress charged with sex trafficking of minors for [[Jeffrey Epstein]].<ref>{{Cite court|litigants=United States v. Ghislaine Maxwell|court=S.D.N.Y.|url=https://www.justice.gov/usao-sdny/press-release/file/1291491/download}}</ref> In December 2021, a jury found her guilty on five of six counts involving sex trafficking of minors,<ref>{{Cite web|url=https://brooklyneagle.com/articles/2021/12/29/ghislaine-maxwell-convicted-in-epstein-sex-abuse-case/|title=Ghislaine Maxwell convicted in Epstein sex abuse case|date=December 29, 2021}}</ref> and in June 2022, she was sentenced to 20 years.<ref name=Walsh>{{cite web |url=https://www.bbc.com/news/articles/cy0glxd0gxko|publisher=BBC News|title=Ghislaine Maxwell loses sex trafficking appeal|author=Aoife Walsh|date=September 17, 2024}}</ref> Her conviction and sentence were upheld on appeal.<ref name=Walsh/>
|-
| [[Sean Combs]] ("Diddy")
|2025
|Convicted
|In 2025, a jury in federal court in New York found [[Sean Combs sexual misconduct allegations|Combs guilty of two counts of violating the Mann Act]]; he was acquitted of sex trafficking and racketeering.<ref>{{cite news |title=Live Updates: Sean Combs Acquitted of Sex Trafficking but Found Guilty on Lesser Charges|url=https://www.nytimes.com/live/2025/07/02/arts/sean-combs-diddy-trial-jury|newspaper=New York Times|date=July 2, 2025}}</ref>
|}

===Individuals considered for prosecution under the Act===
<!-- PLEASE READ BEFORE EDITING THIS SECTION: Only add individuals to this section if you have a proper, reliable source that explicitly states they were prosecuted under the Mann Act. -->
* [[Anwar al-Awlaki]], an American citizen, Islamist cleric, and [[al-Qaeda]] organizer, was investigated for violations of the Mann Act, authorities primarily wanting to arrest him for his ties to the [[hijackers in the September 11 attacks|9/11 hijackers]], but left the United States for Yemen before he could be detained.<ref name= how>{{cite news |url=https://abcnews.go.com/Blotter/FtHoodInvestigation/anwar-awlaki/story?id=9200720&page=1 |last=Rhee|first=Joseph|author2=Mark Schone|date=November 30, 2009|publisher=ABC News |title= How Anwar Awlaki Got Away: Fort Hood Investigation |work=ABC News |access-date= December 1, 2009}}</ref>
* [[Dušan Popov]], a World War II Allied double agent with a "[[James Bond]]" lifestyle, was threatened with arrest under the Mann Act.<ref name="CG">{{cite book
|url=https://books.google.com/books?id=Tu86exHKPvMC&q=du%C5%A1ko+popov+mann+act&pg=RA3-PA272
|author=Gentry, Curt
|year=2001
|page=272
|title=J. Edgar Hoover: The Man and the Secrets
|publisher=W. W. Norton & Company
|isbn=978-0-393-32128-9}}</ref>
* Individuals associated with the [[Emperors Club VIP]] prostitution ring, one of whose more prominent clients was [[Eliot Spitzer]] while he was [[governor of New York]].<ref name=nyt20080310>{{cite news |title=Spitzer Is Linked to Prostitution Ring |url=https://www.nytimes.com/2008/03/10/nyregion/10cnd-spitzer.html |work=The New York Times |date= March 10, 2008|access-date= August 22, 2010 |first1=Danny |last1=Hakim |first2=William K. |last2=Rashbaum}}</ref>
* Individuals associated with the [[Fundamentalist Church of Jesus Christ of Latter-Day Saints]] (FLDS), such as [[Warren Jeffs]] and [[Merril Jessop]] have refused to answer questions during [[Deposition (law)|depositions]] and court hearings, citing the [[Fifth Amendment to the United States Constitution|5th Amendment]], over concerns of [[self-incrimination]] related to "potential state investigation still ongoing, as well as criminal investigations under the Mann Act out of the U.S. Attorney's Office."<ref>{{cite news |last=Anthony |first=Paul |title=FLDS leader invokes 5th in deposition: He pleads it more than 250 times, court transcript says |work=[[San Angelo Standard-Times]] |date=January 28, 2009 |url=http://www.deseretnews.com/article/0,5143,705280971,00.html |access-date=July 24, 2009 |url-status=dead |archive-url=https://web.archive.org/web/20090205062419/http://deseretnews.com/article/0%2C5143%2C705280971%2C00.html |archive-date=February 5, 2009 }}</ref>

===Mann Act case decisions by the United States Supreme Court===
* ''[[Hoke v. United States]]'', {{ussc|227|308|1913}}. The Court held that Congress could not regulate prostitution ''per se,'' as that was strictly the province of the states. Congress could, however, regulate interstate travel for purposes of prostitution or "immoral purposes".
* ''[[Athanasaw v. United States]]'', {{ussc|227|326|1913}}. The Court decided that the law was not limited strictly to prostitution, but to "debauchery" as well.<ref>[[:wikisource:Louis Athanasaw v. United States]]</ref><ref>{{cite web |url=https://caselaw.findlaw.com/us-supreme-court/227/326.html |title=Athanasaw v. United States |website=Findlaw}}</ref>
* {{cite court | litigants=Holte v. United States | vol=236 | reporter=U.S. | opinion=14 | date=1915 | url=https://caselaw.findlaw.com/us-supreme-court/236/140.html | postscript=none}} In a 1915 ruling, the Court determined that it is not impossible for a victim of the Act to be charged with conspiracy under specific circumstances. The requirements for conspiracy by a victim of the Act were limited in a 1932 ruling.{{cite court | litigants=Gebardi v. United States | vol=287 | reporter=U.S. | opinion=112 | date=1932 | url=https://www.law.cornell.edu/supremecourt/text/287/112 | postscript=none}}
* ''[[Caminetti v. United States]]'', {{ussc|242|470|1917}}. In 1917, the Court decided that the Mann Act did not apply strictly to purposes of prostitution, but to other noncommercial consensual sexual liaisons; thus consensual extramarital sex fell within the category of "immoral sex".
*  {{cite court | litigants=Gebardi v. United States | vol=287 | reporter=U.S. | opinion=112 | date=1932 | url=https://www.law.cornell.edu/supremecourt/text/287/112 | postscript=none}} In 1932, the Court ruled that consent by the victim to their own transportation does not constitute conspiracy or culpability under the Act.
* ''[[Cleveland v. United States (1946)|Cleveland v. United States]]'', {{ussc|329|14|1946}}. The Court decided that a man can be prosecuted under the Mann Act even when married to the woman if the marriage is polygamous; therefore, in 1946, polygamous marriage was determined to be an "immoral purpose".
* ''[[Bell v. United States]]'', {{ussc|349|81|1955}}. The Court decided that simultaneous transportation of two women across state lines constituted only one violation of the Mann Act, not two violations.
* {{cite court | litigants=Wyatt v. United States | vol=362 | reporter=U.S. | opinion=525 | date=1960 | url=https://caselaw.findlaw.com/us-supreme-court/362/525.html | postscript=none}} The Court affirmed that a victim can be compelled to testify against a spouse who violated the Act, in exception to the common law spousal privilege rule.