A bill to recover from employers and insurers the cost of treating people with asbestos-related diseases is outside the Welsh Assembly’s legislative competence, the Supreme Court has ruled.

The Recovery of Medical Costs for Asbestos Diseases (Wales) Bill had been referred to the Supreme Court by the counsel general for Wales to resolve ‘novel and important’ issues.

Lord chief justice Lord Thomas said ‘the issue plainly arises as to how the court is to treat the judgement of the Welsh Assembly, in contradistinction to the UK parliament in relation to a matter of social and economic policy such as the funding of a national health service’.

Assembly presiding officer Dame Rosemary Butler called for ‘greater clarity’ so everyone understood what laws the assembly could pass. Her concern was echoed by Labour member Mick Antoniw, who presented the bill. He said there is now an ‘uncertainty around what we can and can’t do’.