"The threat to Australia and to Australians from this is real, and growing. So this week, the government announced a series of measures that will strengthen our national security." Australia's Prime Minister Tony Abbott has addressed the nation in a YouTube video called "Keeping Australia Safe And Secure", where he justifies the government's proposed data retention scheme.
Alongside $630 million over four years in extra funding "to boost the counter-terrorism capacity" of the AFP, ASIO and ASIS, is the ability to "monitor, arrest and prosecute" anyone engaging in terrorist activity abroad and travelling from Australia for that activity — "people who have been involved with terrorist groups". Part of that ability comes through the increased monitoring of Australians' phone and online information:
"As part of these plans, we want telecommunications companies to keep their data. We don't want to collect new data, but to ensure the limited data already collected can be accessed by authorities against those who have, or are planning, to commit crimes."
You can skip directly to Prime Minister Abbott's comments on data retention here. There is no detail in Abbott's speech as to specifically which crimes are being targeted. In an interview on data retention with iTnews, Communications Minister Malcolm Turnbull said that the policy wouldn't be targeted at copyright infringement, after an apparently poorly chosen example where he discussed the procedure of rights-holders monitoring pirates' IP addresses.
The entire speech is coached under the suggestion that these measures are being enacted to stem the tide of international terrorism: "We are determined to stop the flow of money that supports these extremists in their activities. These are measures to make 23 million Australians safer." [YouTube]