Specifically, MSPs will be asked to carry a further Legislative Consent Motion (or LCM, formerly known as a Sewel motion).
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2.
Would that not entitle the UK Parliament and Government to be consulted, Sewel style, about the content of said referendum?
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3.
Against that, the Sewel Convention (named after Lord (John) Sewel who piloted the 1998 Act through the Upper house as a minister) is designed to elide cross-border arguments.