SCOTLAND's political scene seems to hold a new surprise every week. Just a fortnight after the elation the SNP must have experienced in the wake of System Three's historic poll for The Herald which put it ahead of Labour for the first time, a new survey puts support in favour of Labour's devolved Scottish Parliament at 58%. Independence as a constitutional option gains only a little over half this level of support at 34%. Confused?

Well, it may not be surprising that politicians, commentators and pundits alike are all arguing furiously over the reasons for the current trends. So what are the facts that can be clearly identified? Firstly, for elections to Westminster, Labour is doing very well with the SNP around 15% behind. Secondly, for a Scottish Parliament, with a new electoral system, the SNP closes the gap to Labour, a trend identified over a number of months by System Three and other polls. Thirdly, surveys so far this year have confirmed that support for devolution is a good deal ahead of that for independence.

With the lack of in-depth interviews, such opinion poll findings only scratch at the surface of voters' intentions and throw up considerably more questions than they answer. However, one thing is clear. The mould of Scottish politics has been re-shaped. I use re-shaped rather than broken because the ''British'' element of Scottish politics, as measured by voting intentions for Westminster, remains largely in line with what analysts would expect to be happening. Added to this is a new element in Scottish political culture - the ability to express purely Scottish political choices.

Voting intentions have before always by necessity involved a dual Scottish and British perspective, no matter what influences were brought to bear on the choices made by voters. Now, the creation of a Scottish Parliament has provided voters with a new political framework. This allows the seemingly contradictory pattern of voter intentions showed in recent polls.

It also shows more starkly the implications of a trend long identified by the pollsters over the last two decades, namely that there is no strict match between the parties voters choose and the constitutional option they prefer. The fact that some SNP supporters have always favoured devolution and that some Labour supporters have always supported independence has tended to have been brushed under the carpet by the politicians. Their failure to understand the voters' messages is now being shown in their difficulty in responding to the current situation.

Clearly there are many voters who want a credible alternative choice in the elections for a Scottish Parliament. The SNP needs to face up to the fact that voters may simply, for now at least, want it to run the new Scottish Parliament without moving to full independence. Such a choice, if that is what it is in some voters' minds, is surely as rational and reasonable as any other. In fact it has all the hallmarks of the ''Canny Scot'' that we all know and love. The SNP is not tried and tested. Could voters be suggesting that the SNP should be given an opportunity of running this new Parliament before they decide whether they like the thought of full independence?)

At this stage we do not know the answer to that question without further research. There is food for thought for everyone. The status quo as offered in previous polls is no longer that. We are in a state of flux. The warning signs are there for both the SNP and Labour. The SNP cannot expect to force its independence view on voters without further tests of its ability. It must respond to that. Its increase in support is conditional. For Labour it must react to the fact that according to System Three 29% of its support currently favour independence. In the Scottish Election Study in 1992 that figure was 14%. There is difficulty in comparing different types of survey, but if there is anything in that increase it must be dealt with by Labour or Scotland's future may run out of its hands.

Malcolm Dickson lectures in Politics at the University of Strathclyde