The spectator shoe, also known as co-respondent shoe, is a style of low-heeled, oxford, semi-brogue or full brogue constructed from two contrasting colours, typically having the toe and heel cap and sometimes the lace panels in a darker colour than the main body of the shoe. This style of shoe dates from the nineteenth century but reached the height of popularity during the 1920s and 1930s.
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In the 1920s and 1930s in England, this style was considered too flamboyant for a gentleman, and therefore was called a tasteless style. Because the style was popular among lounge lizards and cads, who were sometimes associated with divorce cases, a nickname for the style was co-respondent shoe, a pun on the colour arrangement on the shoe, and because “co-respondent” is the legal description of a third party caught in flagrante delicto with the guilty party in a case of adultery.
The photo is from this thread - Vintage Spectator Shoes | Page 29 | The Fedora Lounge.