The toll of 49 dead and more injured in mass shootings at two New Zealand mosques has put renewed scrutiny on New Zealand’s gun laws, particularly the debate over restrictions on military-style rifles and high-capacity magazines, which are frequently used in mass shootings worldwide.

Civilians in New Zealand own an estimated 1.2m firearms, according to the 2017 Small Arms Survey. That makes New Zealand’s per capita rate of gun ownership higher than Australia’s, but still far below the US, where there is more than one gun per person in civilian ownership.

The Christchurch shootings highlight “the disparity between New Zealand gun laws and those of other developed nations”, said Philip Alpers, an Australian researcher and the founding director of GunPolicy.org, which tracks gun laws worldwide.

Unlike the UK and Australia, New Zealand does not ban the ownership of semi-automatic assault weapons. Most guns can be legally sold on the internet or through newspaper ads. Any person aged 16 or over with an entry-level firearm licence can keep any number of common rifles and shotguns without having to register them.

“New Zealand’s decision not to register 96% of civilian firearms makes it a standout exception, alone with the United States and Canada,” Alpers said.

New Zealand’s prime minister, Jacinda Ardern, said after Friday’s massacre that she would tighten the country’s gun laws, and that she would consider banning semi-automatic weapons altogether.

“I can tell you one thing right now. Our gun laws will change,” she said.

There has been renewed debate in New Zealand over the past year about what police say are loopholes in the way military-style semi-automatic (MSSA) rifles are defined by law. Possession of MSSA rifles is supposed to be subject to a higher level of scrutiny, and there are only about 15,000 registered in civilian hands in 2018.

The legal definition of MSSA firearms, however, means that guns with slightly different features but virtually the same function fall outside the stricter regulations. Both police and firearms enthusiasts noted that a rifle could be transformed into an MSSA simply by adding a larger-capacity magazine.

A review of New Zealand’s gun laws commissioned by police officials in 1997 recommended that MSSA rifles be banned and subject to a mandatory buyback. None of the review’s recommendations were adopted, Alpers said.

The country’s gun laws are largely unchanged since 1992, when controls were tightened after the 1990 Aramoana massacre, in which a man killed 13 people with a semi-automatic rifle.

A briefing document sent recently to a New Zealand minister complained that gaps in the law had already been exploited in violent incidents, and noted that “purchase of high-capacity magazines is unregulated and does not require a firearms licence”, Stuff.co.nz reported last year.

The country’s former prime minister Helen Clark called for tougher gun laws on Friday. Speaking to ABC News she said: “We do have gun control. People have to be fit and proper persons to have guns, but undoubtedly the law can be strengthened and improved.

“Personally, I would be surprised if the New Zealand parliament didn’t accept that challenge head on to strengthen the law. I think we could do better and a tragedy like this brings that forward as a priority.”

Additional reporting by Matt Weaver

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