Key Points:

The police have cleared Winston Peters' New Zealand First party of any wrong-doing in its incorrect donations returns last year.

Police say "no offence" was committed and have closed their investigation - ending the inquiries into the NZ First donations controversy.

Mr Peters learned he was cleared as he waited to watch the start of the Melbourne Cup in a corporate box at Ellerslie racecourse.

Mr Peters said he always knew the allegations were baseless, was disappointed the clearance had come so late in the campaign but still believed he could get NZ First over the 5 per cent threshold and back into Parliament.

"Trust the police to wait until just before the Melbourne cup," he said.

The police investigation began in September after Act leader Rodney Hide MP complained alleging the NZ First return of party donations for 2007 was false and that the party secretary had therefore committed an offence under s214G of the Electoral Act.

The 2007 return of party donations was lodged on 16 May 2008.

Police said having assessed a range of information from various sources, and having considered the elements of the offence, they were satisfied that no offence was committed.

Police do not intend to make further enquiries into this matter.

The date of the alleged offence was 16 May 2008 being the day that the return of party donations was made by NZ First to the Electoral Commission. The offence has a six month time limit for bringing a prosecution which expired on 16 November 2008.