The lord chief justice has called for judicial engagement in the drafting of new devolution bills that will be brought forward by the next parliament.

‘A lot of thought has to be given to the way in which the judicial system interacts both locally in Edinburgh, Cardiff, Belfast and from the perspective of the UK as a whole,’ Lord Thomas of Cwmgiedd said.

‘This is going to be quite a difficult task. Our courts have never really had to make constitutional adjudications… the very complexity of modern government and the difficulty in drafting [legislation] is something where we need a lot more time to think through how we are to deal with disputes I fear will inevitably arise.’

Citing the Welsh Assembly’s powers to enact primary legislation, which it acquired in 2011, Lord Thomas said: ‘[The assembly] has begun to enact law which is different from that in England in matters that affect the work of the courts such as family law and, in the immediate future, the law of landlord and tenant.

‘For this reason, there is an urgent need to establish mechanisms through which the courts can give effect to the drafting and implementation of these laws in a manner similar… in relation to Westminster legislation.’

The Ministry of Justice, Lord Thomas pointed out, has been proposing changes to the Civil Procedure Rules arising out of changes to primary legislation. ‘It will be important to ensure that similar mechanisms likewise exist for Wales, so the changes to primary legislation in Wales are followed through, where necessary, in the rules.’

The Wales committee of the Law Society welcomed Lord Thomas’s comments identifying the need for distinct mechanisms for courts to implement uniquely Welsh law.

Thomas was speaking on the relationship between the judiciary, executive and parliament at an event held by the Institute for Government in London on Monday.

Direct judicial engagement, he said, could strengthen access to justice, help to make better law, and modernise and reform the law, which would be of direct benefit to all citizens, ‘and not merely a matter for “constitutional nerds”’.

‘The aim of the judiciary is not to pass judgement on the merit of the proposals,’ he said. ‘It is to ensure that, if the proposals go ahead, they will work as well as they possibly can, or to identify the pitfalls so that, if possible, they can be rectified.’

The Legal Aid, Sentencing and Punishment of Offenders Act 2012, he noted, was a good example where, as a result of judicial cooperation, ‘the government was able to make a better assessment of the likely implications of [changes to the sentencing regime] and ensure sentencing reforms were workable’.

Thomas highlighted other areas for engagement, such as making the legal system more cost-effective. In civil litigation, for instance, he said disclosure of documentation was a serious problem, especially since the advent of modern methods of communication, particularly email, had massively increased the amount of documentation relevant to a dispute.

Thomas also called for ‘root and branch reform’ in legislative procedure, as ‘an awful lot of money is spent on rectifying errors that occurred in sensible legislation because it is scattered through so many different pieces’. The Extradition Act, for instance, was ‘one very good example of something that is now highly complex and it’s very easy to make mistakes’.

‘It is something in which we ought to engage, and we ought to engage as to how we ensure that when we make amendments, they are carried into legislation,’ he said.