Marewa Glovera
© Newshub
Dr Marewa Glovera, an Auckland-based tobacco researcher.
A tobacco researcher's claim that bodies will heal from exposure to secondhand smoke left MPs aghast during submissions on a proposed law to ban smoking in cars.

Dr Marewa Glover, an Auckland-based tobacco researcher, said the proposed law was unnecessary, because exposure to secondhand smoke is "far greater in the home".

"There is more time spent there, and it's more consistent over many more years," she said, adding that time spent in cars is "fleeting".

Dr Glover went on to admit she used to smoke cigarettes, and has been smoke-free for more than 20 years. She said evidence suggests she will now "live as if I had never smoked".

"In tobacco control over 35 years, we have exaggerated the effects deliberately to scare people off smoking," she told the Health Select Committee on Wednesday.

"What we didn't realise, was that years down the track, we'd be in this situation where everyone believed what we said and are now taking these extreme, punitive measures, when the evidence does not support the need for it."

Dr Glover said what people "miss is that our bodies heal, so even if we are temporarily exposed, we heal from that".

Her comments sparked sharp reactions from committee members, including Labour MP Liz Craig who told the researcher she would "agree to disagree".

National's Matt Doocey labelled the researcher's claims "outrageous".

"So, your proposition today is that it's okay for kids to be forced to breathe in their parents' secondhand smoke, because overtime they'll heal? I mean, that's just outrageous," he said.

Dr Glover responded: "No, my proposition is, if you don't want people smoking around children, please put the money, time and effort into effective interventions to help those parents quit."

She added: "This proposal is a waste of time - it's not going to make any difference."

The Smoke-free Environments (Prohibiting Smoking in Motor Vehicles Carry Children) Amendment Bill was announced in February by Associate Minister of Health Jenny Salesa.

She said it was important to safeguarding the health of children, with Māori and Pacific kids most vulnerable to secondhand smoke in vehicles.

Her Bill proposes banning smoking in vehicles carrying anyone under the age of 18 years old. But vehicles parked on the road being used as a dwelling would be exempt.

That exemption was the main point of opposition from other submitters to the select committee.

Prudence Stone, chief executive of the Public Health Association of New Zealand, began her submission by slamming Dr Glover's comments.

"What a strange precedent that has been set by the previous submitter," she said.

"For years, the smoke-free sector has done what it can to help kids from smoking in cars...Without the backbone of legislation young people will be at risk."

Stone went on to say she rejected the clause in the Bill that would exempt vehicles being used as a dwelling.

Labour MP and committee chair Louisa Wall explained how the clause was necessary because it differentiates between public and private spaces.

However, Victoria University of Wellington student Meghan Grant, in her submission, made the point that smoking in cars "brings private property into the public space".

MPs nodded in agreement.

In Canada, smoking is prohibited if there are children less than 16 years of age in the vehicle. Similar rules apply in Australia and the UK.

The Government has a goal of making New Zealand smoke-free by 2025, but some 600,000 Kiwis are still smoking, according to Smoke Free New Zealand.

The target was set off the back of findings from the Māori Affairs Select Committee in 2010 which sparked an inquiry into the tobacco industry and the effects of tobacco use on Māori.

The inquiry outlined measures "to remove tobacco from our country's future in order to preserve Māori culture for younger generations".

There are fears the proposed ban on smoking in cars with kids would disproportionately target Māori.

Dr Glover earlier told The AM Show that the Bill is "discriminatory" and "will negatively impact the poor and Māori the most".

The AM Show's campaign to ban smoking in cars with kids has been signed by more than 69,000 people.