In February 1895, angered by the apparent ongoing homosexual relationship between Oscar Wilde and his son Alfred, Queensberry left a calling card reading "For Oscar Wilde, posing Somdomite [sic]" at Wilde's club.
Wilde sued for criminal libel, leading to Queensberry's arrest.

The trial opened at the Old Bailey on 3 April 1895 before Justice Richard Henn Collins amid scenes of near hysteria both in the press and the public galleries.
Queensberry's lawyers, headed by barrister Edward Carson, presented Wilde as a vicious older man who seduced innocent young boys into a life of degenerate homosexuality.
Wilde dropped the libel case when Queensberry's lawyers informed the court that they intended to call several male prostitutes as witnesses to testify that they had had sex with Wilde.
According to the Libel Act 1843, proving the truth of the accusation and a public interest in its exposure was a defense against a libel charge, and Wilde's lawyers concluded that the prostitutes' testimony was likely to do that.
Queensberry won a counterclaim against Wilde for the expenses he had incurred on lawyers and private detectives in organizing his defense.
Wilde was left bankrupt; his assets were seized and sold at auction to pay the claim.

Queensberry then sent the evidence collected by his detectives to Scotland Yard, which resulted in Wilde being charged and convicted of gross indecency under the Criminal Law Amendment Act 1885 and sentenced to two years' hard labour.
His health and reputation destroyed, Wilde went into exile in France.

Queensberry died on 31 January 1900.
Ten months later, Oscar Wilde died at the Hotel d'Alsace in Paris.
In February 1895, angered by the apparent ongoing homosexual relationship between Oscar Wilde and his son Alfred, Queensberry left a calling card reading "For Oscar Wilde, posing Somdomite [sic]" at Wilde's club. Wilde sued for criminal libel, leading to Queensberry's arrest.
The trial opened at the Old Bailey on 3 April 1895 before Justice Richard Henn Collins amid scenes of near hysteria both in the press and the public galleries. Queensberry's lawyers, headed by barrister Edward Carson, presented Wilde as a vicious older man who seduced innocent young boys into a life of degenerate homosexuality. Wilde dropped the libel case when Queensberry's lawyers informed the court that they intended to call several male prostitutes as witnesses to testify that they had had sex with Wilde. According to the Libel Act 1843, proving the truth of the accusation and a public interest in its exposure was a defense against a libel charge, and Wilde's lawyers concluded that the prostitutes' testimony was likely to do that. Queensberry won a counterclaim against Wilde for the expenses he had incurred on lawyers and private detectives in organizing his defense. Wilde was left bankrupt; his assets were seized and sold at auction to pay the claim.
Queensberry then sent the evidence collected by his detectives to Scotland Yard, which resulted in Wilde being charged and convicted of gross indecency under the Criminal Law Amendment Act 1885 and sentenced to two years' hard labour. His health and reputation destroyed, Wilde went into exile in France.
Queensberry died on 31 January 1900. Ten months later, Oscar Wilde died at the Hotel d'Alsace in Paris.
John Douglas, 9th Marquess of Queensberry