Aussies are rustling up a class-action after children and adults wrongly arrested and detained because of systemic computer problems.

A team of Sydney lawyers is planning a law suit over a legal system computer flaw that has led to dozens of people, including children, being wrongfully arrested and often falsely imprisoned. NSW Police paid more than $2.7 million in the last year to 22 people, including five juveniles, after officers made unlawful arrests wrongly alleging bail condition breaches.

But it turned out that the police computer system did not contain accurate information. The government has ignored requests to fix the problem and opted for the Kafkaesque approach of just arresting people.

Edward Santow, the chief executive of the Public Interest Advocacy Centre told the Sydney Morning Herald that the group had asked for the database to be fixed 10 times and each time been ignored. A lawsuit was seen as the only way to get the government to pay any attention to the problem, he said.

The problem was that when a bail condition such as an 8pm curfew expired or was removed, the information was not communicated to police, who then arrested and, in many cases, locked up people up. ''They go before a court. The court records are accurate and the police say 'sorry' and the state ends up with a compensation payment on its hands.''