Attorney-General Philip Ruddock said the new rules were the biggest changes to Australia's phone-tapping laws in 27 years, and updated legislation to take account of new technology.
But civil liberties groups and the minority Australian Democrats party said the new laws went too far.
''These powers allow police for the first time to tap the phones of innocent third parties, people who are not even suspected of a criminal offence,'' Australian Council of Civil Liberties spokesman Cameron Murphy said.
Australia has gradually toughened its security laws following the September 11, 2001, attacks on the United States, with law enforcement agencies receiving powers to detain people without charge for extended periods if they are suspected of having knowledge of an attack.
In December last year, Sydney's beaches were rocked by race riots after rival gangs of white supremacists and middle-eastern youths used mobile phone text, or SMS, messages to call their supporters together.
The new laws allow police, intelligence agencies and investigating authorities to secretly retrieve e-mails and text messages from phone companies and Internet service providers.
Murphy said the laws would target lawyers and journalists, and allow authorities to go ''on fishing expeditions'' to find evidence of criminal behaviour or hunt down sources of leaks.
Australian Democrats Senator Natasha Stott Despoja said the new rules would allow bodies like the Australian Securities and Investment Commission and the tax office to intercept conversations which are currently protected by law.
''Conversations between a person and their lawyer, their doctor, their religious leader or their member of parliament can now be intercepted with no consideration for professional privilege,'' Stott Despoja said in a statement.
Ruddock defended the laws, saying they gave authorities the power to fight serious crime.
''They ensure law enforcement and security have the investigative tools to continue the fight against serious crime and terrorist activity,'' he said in a statement.
REUTERS LR SND1220