Police have confirmed they are investigating an abusive email sent to the Green Party MP Sue Bradford during the referendum on smacking.
Ms Bradford says she has received an increased number of abusive emails and phone calls since the beginning of the referendum.
Ms Bradford has also been the subject of a threat posted on the social networking site 'Twitter', which said she is a "good candidate for New Zealand's first political assassination".
The holder of the account from which the threat was made, Henk Van Helmond, says his account was hacked and he has since apologised to Ms Bradford. A similar comment was posted on another website hosted by Mr Van Helmond in 2007.
The MP says she's the target of suppressed rage from people who want to assault their children.
A police spokesperson says officers are investigating a complaint from Ms Bradford about an email she received three or four weeks ago.
Ms Bradford says she believes police are intending to prosecute over the email. Police are not commenting on whether charges will be laid.
The director of the lobby group Family First, Bob McCoskrie, says he doesn't condone the abusive emails being sent to Sue Bradford.
Mr McCoskrie says his group has been conducting an email campaign on MPs about the issue, but that's not connected to the abuse against Ms Bradford.
He says he always asks supporters to be polite when emailing politicians.
The organiser of the referendum on smacking, Larry Baldock, says he doesn't condone the abusive emails being sent to Ms Bradford.
He says he and his supporters have also been the target of abusive phone calls and emails.