National is open to expanding its proposed ban on the right to silence for child killers, depending on legal advice. 

The party's proposing a law change that would send witnesses of child killings to prison for up to 10 years, if they don't reveal who was responsible. 

National's Nicola Willis has voiced support for this policy and says it's 'unlikely' this will result in false testimonies. 

"It is always the case that the justice system has to sift through the testimony of witnesses and perpetrators and judge the voracity of people's statements. That's what the justice system deals with - day in, day out." 

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