He grew up in the Woolshed near Beechworth and was a childhood friend of gang member Joe Byrne. He was a friend of the outlaws, but gained the trust of Police Superintendent Francis Hare. Traditional accounts of the Kelly Gang portray him as a traitor, but many of the police suspected he was a double agent working for the Kelly Gang.
Detective Mick Ward actively worked to increase tensions between Sherritt and the Kelly Gang.
Policemen were sent to guard Sherrit, but their presence convinced the gang he was a traitor. On the 26 June 1880 Sherritt was at home with his wife, mother-in-law and four policemen, Constables Armstrong, Alexander, Ducross, and Dowling.
A neighbour, Antone Weekes, who had reportedly been handcuffed and held hostage by Joe Byrne and Dan Kelly, called out "Aaron". At the front door of Sherritt's hut.
When Sherritt answered it, Joe Byrne shot him point-blank in the chest.
The gang then held four police officers assigned to protect Aaron captive in the house for 12 hours before they stole back into the bush.
Within a couple of days, Joe Byrne was himself killed in a shootout between the gang and the police at Glenrowan. Ned Kelly was the only one to survive to stand trial. He was found guilty and hanged on 11 November 1880.