MPs have heard differing accounts of whether a proposed law change will extend the powers of the country's electronic spy agency.
The Intelligence and Security Committee, chaired by Prime Minister John Key, has begun hearing submissions on legislation making it legal for the Government Communications Security Bureau (GCSB) to monitor New Zealanders.
Appearing on behalf of the Law Society, Rodney Harrison, QC, told the committee on Tuesday the bill extends the powers of the GCSB.
Mr Harrison said the public needs to know what activities would be conducted under the law change and a review of the law could be handed on to the Law Commission.
However, an academic specialising in security studies, James Veitch, told the committee he supports the law change.
Mr Veitch said it does not expand the agency's powers, but clarifies the law and brings into the public arena what is already happening.
PM to face Dotcom
John Key faces the prospect of a confrontation with Kim Dotcom when the internet businessman appears before the Intelligence and Security Committee on Wednesday.
Mr Dotcom is suing the GCSB for damages after his lawyers discovered that the German national with New Zealand residency was being spied on, which is currently against the law.
Green Party co-leader Russel Norman said Mr Dotcom is the one person who has sufficient resources to get to the bottom of the GCSB's involvement in his case.
Dr Norman said other people would not know they had been spied on or, if they did, would not be able to afford to go to court.
Labour leader David Shearer said he is looking forward to watching the dynamics at the hearings - especially between Mr Dotcom and John Banks, a member of the intelligence committee.
"You've got Kim Dotcom meeting John Banks for the first time, perhaps since he shared a helicopter with him. And John Key meeting one of his constituents for perhaps the first time - one of those people that he forgot that he had in his electorate."
Mr Banks declared anonymous donations in his 2010 Auckland mayoral campaign that were later revealed to have come from Kim Dotcom.
John Key said he is relaxed about facing Mr Dotcom.