THIS weekend, the Scottish Parliament that many fought for, some never wanted, and more than 70 per cent of the Scottish electorate voted for is 20 years old and over the last week many of the leading figures of devolution have been speaking to The Herald to mark the occasion. As you would expect, there has been little consensus: the lessons of the last two decades are not clear-cut, the political records are mixed, and the signposts for the future uncertain.

Where most observers do agree is on some of the high-profile policy successes. Within its first year, Holyrood repealed the reviled Section 28 law, which effectively prohibited any positive discussion of homosexuality in schools. The move was not without resistance, but it was an early, positive sign that the Scottish Parliament was going to do its own thing and speak with a different voice.

There are many other achievements Scottish parliamentarians can be proud of, even if some of the policies are still a work in progress: the introduction of guaranteed nursery provision for three and four-year-olds, for example. Other policies will have to await the test of time – we are still waiting to see, for instance, whether the minimum pricing of alcohol will have any profound effect on Scotland’s bad habits.

As for the country's two great public services – health and education – the picture is mixed. Compare the pressures on the Scottish NHS ten years ago with the pressures on it now and it is clear there is a deepening crisis. Many teachers would use the same words about schools – indeed, this newspaper reports today that nearly half of Scottish teachers have seen a medical professional in the last year as a result of the strain of their job – and certainly it is in schools and hospitals that some of the deepest disappointment with Scottish governments has been felt. Nigel Smith, who spearheaded the push for devolution 20 years ago, told The Herald this week it was in these big areas of health and education that he felt most disappointment with the Parliament and it is hard to dispute his assessment: six out of ten at best.

One way to improve the situation would be for the parliament to rediscover its radical voice or at least a robust system for testing legislation. One of the lessons of the debacle of the Offensive Behaviour of Football Act – which almost no one liked and which failed to work – is that a government with tight control over its backbenchers, coupled to a committee system that has an in-built majority for the governing party, does not always lead to good and coherent legislation. It might be useful to remember that the parliament was specifically set up to be multi-party and pluralistic and the tight discipline of the SNP has not always been good for it.

The current dominance of the SNP is also a reflection of the way politics has changed in the last 20 years. When the parliament was established, Labour’s pre-eminence in Scotland looked as strong as ever but its decline has coincided with independence becoming the central preoccupation of Scottish political life.

Has this dominance of independence been good for the parliament? Not always, particularly when issues such as the crisis in the NHS become a proxy for the debate between nationalists and unionists. The constitutional debate has also led to friction between Holyrood and Westminster that does not always reflect reality. This week, the First Minister warned that devolution was under threat from what she called creeping centralisation by the UK Government, but the reality is that successive governments in London have respected the conventions of devolution and expanded them.

If some agreement is to be found, it is in the fact that devolution as a process has been a success. The foundation of the parliament 20 years ago was the most significant development in our political history since 1707 and, while its development since then has been imperfect, it has allowed Scottish governments to try to find distinctly Scottish answers to Scottish questions. That, along with the 20th anniversary, is a cause for celebration.