If this connection between certain tattoos and violent deaths were to hold true beyond the study region, my guess is that other tattoos might also be related to other individuals or symbols of anti-establishment movements.
Although Ned Kelly (1855-1880) died in the 19th century, he remains a powerful and controversial figure in Austalia. Of Irish heritage, Kelly came to represent Irish-Australian resistance against the British ruling class at the time. He was a member of a gang that cattle rustled, robbed banks and committed other crimes.
When police were called in, Kelly often had the upper hand. In one famous incident, he overpowered a policeman, sat on top of him, and humiliated the official by riding him like a horse. During a gunfight at Stringybark Creek in 1878, he is thought to have shot and killed three police officers. Kelly's brief and violent life was cut short by execution at Melbourne, Victoria.
Kelly's daring and notoriety turned him into a cult icon in Australia and elsewhere. In the United States, a number of singers, including Johnny Cash and Waylon Jennings, crooned about the Irish-Oz rebel.