I've just discovered this resource, collected and digitised by the Harvard Law School Library.
Broadsides were published in Britain in the 18th and 19th centuries as street literature for the lower classes. These one-sided sheets usually included an illustration, an account of the crime and details of the criminal's confession. A verse cautioning the reader to avoid the fate of the perpetrator was also common.
Harvard's collection includes more than 500 broadsides spanning 1707 to 1891 and covering crimes such as assault, stealing, murder, robbery and treason. Many of the broadsides describe the results of sentences handed down at the Old Bailey.