Scottish Statutory Instrument

A Scottish Statutory Instrument (Scottish Gaelic: Ionnsramaid Reachdail na h-Alba; SSI) is subordinate legislation made by the Scottish Ministers or a regulatory authority in exercise of powers delegated by an Act of the Scottish Parliament. SSIs are the main form of subordinate legislation in Scotland, being used by default to exercise powers delegated to the Scottish Ministers, the Lord Advocate, the High Court of Justiciary, the Court of Session, and the Queen-in-Council.

The Interpretation and Legislative Reform (Scotland) Act 2010 defines the Scottish Statutory Instrument. Before this Act, SSIs were governed by the Statutory Instruments Act 1946, which continues to govern UK Statutory Instruments.

SSIs, and the power to enable the creation of subordinate legislation in general, are not mentioned in the original text of the Scotland Act 1998, which devolved powers to the Scottish Parliament. Rather, this power is implied by the statement that Acts of the Scottish Parliament are law to the extent that they are not "outside the legislative competence of the Parliament," without any subsequent reservation of the power to make subordinate legislation.

Before Scottish devolution, subordinate legislation applying only to Scotland was published as a subseries of the larger UK statutory instrument (SI) series. This subseries is now used for SIs which deal with reserved matters in relation to Scotland.

An SSI is made, with some exceptions, by a body exercising executive governmental functions – that is, a body responsible for putting the law into effect ("executing" the law) rather than a body responsible for defining the law (the legislature) or a body responsible for interpreting the law (the judicature). As a result, an SSI will provide specific details on how an Act should be put into effect, and may amend existing Acts or SSIs to reflect that the law has changed. In other cases, an SSI may repeal parts of the law which had before been impliedly repealed.

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