Three years after the outcry at financial restrictions on independent electoral advertising, the Labour Party has got its way. National has folded on an issue it fought from Opposition, agreeing to restrictions that differ only by degree with the spending limits legislated by the Labour Government.

National's amendment to the Electoral Finance Act has emerged from a select committee of Parliament with a $300,000 limit on the amount "third party" participants can spend to promote an issue to voters. "Third party" is the politicians' term for people or groups of no affiliation who are not standing for election but are moved to spend their own money on a cause close to their heart.

Throughout this long debate over their rights, most people who practise politics or study it avidly have missed the central point. It is this: people who are not avid followers of politics and public issues have their voice effectively muzzled by law that is mined with arcane, pernickity requirements.

They will not recall the precise rules and may be deterred by the bother of dealing with them. If parliamentarians doubt this they should listen to their own debates about, for example, signs on a house fence. Does the cost of the fence count as campaign finance that has to be declared? The select committee has decided it will not count, but how many other pitfalls might there be?

There are a couple of simple rules independent promoters should have to observe, which are easy to understand. One is that they must not urge a vote for or against a named candidate or party because that would circumvent party spending restrictions. The other is that they must clearly identify themselves in any advertisement.

The public should know who is putting an issue in front of them. That rule would have quickly exposed, and probably discouraged, the insidious 2005 campaign by seven Exclusive Brethren that prompted Helen Clark's legislation. But the 2007 act put so much red tape around "third party" promotions that all such participation was effectively stifled from January 1, 2008, until the election that year.

National came to office with a commitment to repeal the act and set about seeking an across-party consensus on the subject. This it has now achieved by inserting a spending restriction in its amendment bill. In return, Labour has agreed that parties need not disclose the identity of donors to their campaigns for donations up to $15,000.

The public stands to lose on both counts. Independent participants will have to worry about financial limits and reporting requirements while less will be known about who is backing the parties seeking power. The parties will be able to spend 10 times as much as independent campaigns as well as enjoying state-funded television time.

The bi-party agreement leaves any non-party organisation that is thinking of promoting or opposing any policy or principle at an election having to register with the Electoral Commission. If it spends more than $100,000 in the three months to the election it will have to file an expense return and it may not spend more than $300,000. If anything in the return is false or misleading it will be audited at its own expense.

There are enough hoops and risks to discourage all but the established lobbies familiar with political regulation. The spending cap and associated rules might permit their continued presence in election campaigns but the novices, the unexpected, the unconventional campaigns that can add an extra dimension to public debate, will be put off.

National has surrendered to the left's fear of money, which is just one possible influence among many in an election. Its bipartisan fix will leave our politics poorer and preserve elections largely for the parties who have conspired to produce this disgraceful discouraging law.