A brawl at a local pub, the Golden Anchor in Saffron Hill, between some English and Italians ended up with the deaths of several people including Michael Harrington. An Italian, Serafino Polioni or Pelizzioni, was arrested and charged with murder. He was sentenced to hang after his trial. An account from The Herts Guardian, 31st December 1864, is reproduced here:
There were doubts over this conviction amongst the Italian community and Henry Negretti took it upon himself to investigate. Below is the account from Murderpedia:
“Mr Negretti, a well-esteemed and reputable member of the local community, had in the past acted as unofficial judge amongst his fellow countrymen. This case puzzled him and he set about investigations. The murder weapon was discovered 20 yards from the pub, but the accused had not been able to leave the building and could not have dropped or thrown it after allegedly stabbing the Englishman. Further questioning revealed that Pelizzioni had been at another pub at the height of the fray and that it was his cousin, a Gregorio Mogni who resembled him, who was responsible. However, despite Mr Negretti’s interventions, Pelizzioni was charged with ‘Wilful Murder’ and sentenced to hang.” Continue reading at Murderpedia
A twelve-part description of the events, trial and the intervention of Henry Negretti is given in here by a descendent of Michael Harrington:
The role played by Henri Negretti is described in Part 10 thereof: