FORMER Green MSP Andy Wightman has become the third parliamentarian to formally back the legal action aiming to establish that Scotland does not need Westminster’s approval for a second independence referendum.

His affidavit supporting the People’s Action on Section 30 has been lodged at the Court of Session, where the action will be heard next week.

SNP MPs Kenny MacAskill and Angus MacNeil last weekend gave their formal backing to the case, which is being led by indy and disability rights campaigner Martin Keatings.

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Wightman’s move means the action now has written backing from politicians in Holyrood and Westminster.

“It is of vital importance for I as a parliamentarian to be as fully informed as possible as to the constitutional framework under which we operate,” said Wightman.

“My role in representing constituents, scrutinising the executive and making laws requires a working knowledge of such a framework.

“In order to fulfil my responsibilities in relation to debate, representations and legislative proposals concerning Scotland’s constitutional future, I need to understand the relevant provisions of the Scotland Act.

“For these reasons, this case is of great significance and value to me.”

READ MORE: Call to law chief to say ‘exactly’ who he represents in Section 30 independence case

Keatings, the convener of Forward as One, whose crowdfunder for the Section 30 action has raised more than £185,000, told The National: “I am pleased that we now have written support from parliamentarians at both parliaments and that they have chosen to stand beside the grassroots in this action.

“It is for each parliamentarian to decide themselves at this stage if they are going to do the same.”

Wightman quit the Scottish Greens last month, hitting out at a lack of debate in the party over transgender and women’s rights. He is expected to stand as an independent at the next Holyrood elections.