The Eliza Armstrong case was a major scandal in the United Kingdom involving a child supposedly bought for prostitution for the purpose of exposing the evils of white slavery. While it achieved its purpose of helping to enable the passage of the Criminal Law Amendment Act 1885, it also brought unintended consequences to its chief perpetrator, William Thomas Stead.
Since the middle of the 19th century, efforts by the Social Purity movement, led by early feminists such as Josephine Butler and others, sought to improve the treatment of women and children in Victorian society. The movement scored a triumph when the Contagious Diseases Acts were repealed under pressure due to their double standard nature and ultimate ineffectiveness.
At the same time, the campaign had also turned towards the problem of prostitution, and with male power over women. By the end of the 1870s, this had become particularly focused on fears that British women were being lured—or abducted—to brothels in the Continent, especially since this was happening to girls barely past the age of consent. Although the age was raised to 13 when amendments to the Offences against the Person Act 1861 were made in 1875, the movement sought to further raise this to at least 16, but Parliament of the United Kingdom was reluctant to make this change.
However, a Criminal Law Amendment Bill to change this was introduced in 1881. While it passed the House of Lords easily in 1883 after a two-year Select Committee study, it stalled twice in the House of Commons. Then in 1885, it was reintroduced for a third time, but again it was threatened to be set aside ultimately because of a political crisis and the upcoming general election that year.