Sean Plunket and Mark Richardson clash over right to silence

The AM Show's sports host Mark Richardson and Magic Talk radio host Sean Plunket clashed on-air over the right to silence on Wednesday.

The two were discussing the issue - which has been in the spotlight after a young boy was severely injured in Flaxmere recently - as part of a panel discussion on The AM Show. 

The four-year-old was found with severe head injuries, with police urging anyone who knows anything about how he was hurt to come forward.

Plunket says it's time the law is changed in cases like this where child abuse is suspected.

The radio host started a petition calling for "meaningful action and legislation to provide police with the powers to deliver justice in cases of child abuse, to compel adults to do the right thing and protect children".

"What we're saying is, Members of Parliament, throw away your politics, be human beings, come together and for goodness sake do something before the election," Plunket told The AM Show on Wednesday. "Pass this law, give police another tool in their toolbox."

Plunket pointed to legislation in Victoria, Australia, that carries a three-year prison penalty for those who fail to provide information to police.

Although The AM Show host Duncan Garner shared Plunket's view that there needed to be a law change, Richardson wasn't convinced, leading to a heated debate over the issue.

"I'm not signing [the petition] unless I can be convinced that this does not open up a slippery slope to removing the right to silence, which I think is an important convention within the law that protects the little guy in New Zealand," Richardson said.

"So you would rather give fisheries officers more power to investigate breaches of quota than you would someone investigating the beating near-death of a child?" Plunket replied, referring to cases where fisheries officers have the power to demand information from people.

Richardson said he wanted police to be able to get to the bottom of the issue, but insisted there was a middle ground between letting authorities investigate and maintaining the legal right to silence. 

His comments received an impassioned rise from Plunket.

"Why do you think the police went public with this case? They went public with this case because the current laws do not give them the power they need to have got to the bottom of this."

Richardson said he took issue with the fact that "it's an emotive discussion" which linked support for the right to silence with a perceived support of child abuse.

"If you are prepared to say, 'no, I believe in the right to silence' people are trying to put 'oh, you support child beating'," he said.

Speaking on Magic Talk on Tuesday, opposition leader Simon Bridges also weighed in on the subject, saying he supported a law change. He said he would "definitely" accept the petition once it has closed for signatures.

As of Wednesday morning, around 600 people have signed in support of the law change.