The Electoral Commission has taken a swipe at the police for an apparent lack of action in investigating and prosecuting electoral law offences and suggests the job be handed over to another agency.
In its report on the 2011 general election, the commission said that although police dealt with simple matters such as dual voting promptly, they did not do so for more complex issues.
"Some are more difficult and complex and the commission is concerned about the priority the police seem able to accord these referrals."
It recommended the Government consider whether procedures should be strengthened, noting that some of the breaches of the Electoral Act were serious and carried heavy penalties.
"Effective and timely investigation and prosecution of electoral offences is critical to ensuring public confidence in the integrity of the democratic process."
One possibility was to hand over the breaches to another enforcement agency or a Crown solicitor to decide whether to prosecute.
Under the Electoral Act, the Electoral Commission must refer to police any matters it believes contravened the law - ranging from failures to file expense returns to electoral fraud.
Last election, there were 24 referrals to the police and 62 complaints about dual voting. Only one of the investigations into those referrals has so far been completed: the Electoral Commission's belief that Prime Minister John Key's hour-long stint hosting on RadioLive was an election programme which breached the Broadcasting Act. On March 30 police announced they would not lay charges because there was insufficient evidence.
A police spokesman said police did take the referrals seriously and gave them "due priority".
"However, priority for these inquiries must be balanced against other serious matters requiring investigation such as sexual offending, armed robbery, burglary and drugs offences."
He said police were happy to discuss other ways of dealing with the referrals "should the Electoral Commission feel there are better ways they can be handled".
A senior detective oversaw the files, which were assigned to the appropriate district where appropriate.
Other cases the police were investigating included a One News bulletin on election day, Green activist Jolyon White for placing stickers on National Party billboards, one person alleged to have voted using a friend's identity and two assaults at polling booths. Others included ads by several candidates including NZ First's Brendan Horan, Labour's Charles Chauvel and Megan Woods, National's Michael Woodhouse and an email from the Maori Party.
Mr Key said the police were the only agency able to look into the referrals.
"The police in New Zealand are the body responsible for administering the law and whether somebody meets the law or breaks the law ... they're the only body who could do that."
* The Electoral Commission has criticised the police for an apparent lack of action in investigating and prosecuting electoral law offences.
* Last election there were 24 referrals to the police and 62 complaints about dual voting.
* Only one of the investigations into those referrals has so far been completed.