Police will be given new powers to frisk people and enter homes without warrants under proposals to overhaul search, seizure and surveillance laws.
But police will also, for the first time, face legal restrictions on their ability to conduct video surveillance and be subject to tighter rules on what they do with material seized as evidence.
The recommendations are among 300 in a Law Commission report calling for a single regime overseeing powers to search homes and individuals, keep suspects under surveillance and seize property.
Though several agencies, including Customs and Fisheries, exercise some degree of these powers, the report is mainly concerned with police, who use them most often.
The 500-page document comes after a five-year review to address several anomalies, including different powers for different agencies and even different powers for the same agency - usually police - depending on the crime being investigated.
These include the ability of customs officers - but not police - to search people while they are executing warrants.
The report says police should have the same power and also an explicit ability to frisk people arriving at scenes if they are believed to be carrying evidence sought or a weapon.
It also questions why police can search a house for drug offences without a warrant, but not for evidence in a murder inquiry, even if delays could mean the evidence is destroyed, concealed or moved elsewhere.
It recommends allowing warrantless searches if there is a reasonable belief there is evidence of a crime that carries a sentence of 14 years' or more jail, such as rape, manslaughter, kidnapping or murder.
Other anomalies include the requirement for police to obtain a warrant to bug a house or place tracking devices on cars, but not to conduct video surveillance.
The report recommends a single set of rules requiring warrants for all electronic surveillance, including visual.
Commission president Sir Geoffrey Palmer said present laws were cumbersome and confusing, with decisions on whether or not something was legal or admissible too often left to the courts to decide after the fact.
"We need clarity, we need consistency, we need order, we need predictability.
"All those things which are traditional, cherished values of the law are, I'm afraid, absent from this area simply because ... successive Parliaments have passed law after law after law but there are still big gaps."
Deputy president Warren Young, who oversaw the report, conceded it gave police more explicit powers in some areas, but said they were often already exercised and then waved through by the courts.
Proposed new powers had also been balanced by new restrictions, such as tighter controls on video surveillance.
Any new law would have to comply with protections against unreasonable search and seizure under the Bill of Rights Act, and searches of people would continue to be more tightly controlled than for properties.
Council for Civil Liberties president Tony Ellis said he had not seen the full report, but he would be concerned at any new coercive powers for police.
Under new commission rules, Cabinet must consider the report and decide whether to implement it within six months.
- The Dominion Post
Should the speed limit be raised to 110kmh on some roads?Related story: 110kmh limit moves closer