For all the sordid and developing details of Eliot Spitzer’s rendezvous with a high-priced prostitute, go to TPM’s excerpt of the actual prosecutor filings on Temeka Rachelle Lewis, "Kristen" and "Client-9." As I write, it’s unclear if Spitzer will resign, but it seems unlikely that he has the political capital neccesary to gut this one out.

His chances of staying in office, however, would vanish if prosecutors charged him under the 1910 Mann Act–known at the time as the White-Slave Taffic Act. Passed at the end of the Progressive era during the height of a moral panic over alleged "white slavery"–the Mann Act banned the interstate transport of women for "immoral purposes." It’s survived numerous court challenges and modifications by Congress over the years, but it’s still on the books. Spitzer arranged for the prostitute’s Amtrak ticket from New York to Washington (and her hotel room), so he could be subject to federal felony charges under the present day incarnation of the Mann Act. Indeed, the four defendants charged last week in the sting that swept up Spitzer were charged under the act.

One of the crowning accomplishments of 19th-century moral crusaders (along with the Comstock Act of 1873), the history of the Mann Act is drenched with racism and political intrigue–from the fantastic images of Arab harems and Chinese hookers used to sell the bill itself to Jack Johnson, the great black boxer, who was prosecuted under the Mann Act for sending his white girlfriend a train ticket. Johnson served a year in Leavenworth.

It’s too soon to know, exactly, what Spitzer did and what criminal charges he faces, if any. But it’s certainly clear that the former NY Attorney General’s record as a public crusader is on the line. It would be a shame if his tough stances against corporate fraud and other white-collar crimes were forever tarred, but there is a cruel historical irony to all this too. The first Progressive era that birthed the Mann Act combined righteous campaigns against government and business corruption with zealous crusades against vice and immorality.

Until now, Eliot Spitzer represented the former, a present-day incarnation of the Progressive era’s best reformers. And now, if only in an uncanny way, he represents the latter too–as one of its victims.