The commission is seeking clarity on the terms 'election advertisement' and 'election programme' after the High Court overturned its decision to ban the parody 'Planet Key' in August 2014, before the last election.
It had ruled the song was an election advertisement, which meant it could not be played on radio, television or online without a statement declaring the singer-songwriter was a promoter.
Commission lawyer Austin Powell told the court today it was important to have a level playing field during an election campaign.
He said there were no longer clear boundaries after the High Court overturned its decisions on the Planet Key song and on Greenpeace's climate voter campaign.
The court ruled in September 2014 that a Greenpeace website which criticised Energy Minister Simon Bridges was not an election advertisement.
The Court of Appeal hearing continues.