In May 1969, Clarrie O'Shea, Victorian Secretary of the Australian Tramway and Motor Omnibus Employees' Association (ATMOEA), was jailed for refusing to pay fines accrued by the union. The fines were imposed by the Conciliation and Arbitration Commission under the penal powers section of the Act, a coercive measure that had been used to large effect against unions since the 1950s. The jailing sparked the largest strike in post-war Australia.
The late 1960s was a time of growing industrial unrest. Union membership had reached a high point of around 60 per cent of all wage earners. Between 1966 and 1968 the number of workers involved in industrial disputes had nearly doubled. Conflict over the use of the penal powers had been growing in the lead up to the 1969 strike, with the unions receiving fines of nearly $300,000.
O'Shea was sent to Pentridge Prison to be incarcerated until the fines were paid. The response from workers across the country was immediate. The following day around half a million people struck or participated in stop-work meetings, demanding the release of O'Shea and repeal of the penal powers. In Victoria, transport ground to a halt, the ports shut down and the electricity supply was disrupted. Even many pubs and cafes were closed by the strike. Over the days that followed, one million workers were involved in action.
The strikes ended after six days, when an anonymous donor paid the outstanding fines and O'Shea was freed. The short strikes had a lasting impact: although the penal powers remained, they were never used again.