The law governing what, where and how police and other agencies can carry out search and surveillance is being reviewed to take new technology into account.
Justice Minister Amy Adams announced the mandatory review into the Search and Surveillance Act on Tuesday, which looks at how the legislation is working and whether changes are needed.
She says part of it will focus on developments in technology, including smart phones, apps, cloud services and social media, which have changed the way people share information.
"When investigating and prosecuting crime, this has changed the type of information that law enforcement agencies may need to access and can pose challenges to their ability to access it. When considering these issues, it's important to take into account the potential implications for people's privacy, as well as other rights the Act recognises."
But the Green Party is warning the review should focus on strengthening Kiwis' rights, rather than extending "dodgy surveillance powers".
"We are concerned that the review is geared towards extending search and surveillance powers rather than constraining them," co-leader Metiria Turei says.
"There is no evidence that justifies broadening existing search and surveillance powers under this Act, which was already notorious for eroding civil liberties and giving sweeping powers to more government agencies than ever before."
She's concerned the review will look at the police's ability to use spy agencies SIS and GCSB, especially since those agencies are already under review.
The Law Commission and Ministry of Justice will ask for public submissions later this year, with the final report due on June 28, 2017.