The Scottish Criminal Jury — 15 Jurors & Simple Majority

This card distinguishes clearly between what is settled statutory fact, what is traditional historical account, and what remains disputed. The existence of the 15-member jury, the historic simple-majority rule, and the 2026 change to a two-thirds threshold are all matters of statute and public record and are treated as settled. The precise historical reasoning behind choosing fifteen jurors specifically, rather than some other number, is treated as traditional account rather than settled fact, because the documentary record from the relevant period is thinner than for more recent reforms. Finally, normative and empirical claims about whether these jury rules produce fairer verdicts, or whether the 2026 change will reduce wrongful convictions or instead let more guilty people walk free, are treated throughout as live, disputed questions on which reasonable, serious people disagree, including within the legal profession itself.

Origins and Historical Development

Scotland's criminal jury has looked different from its English counterpart for a very long time. While England and most of the common-law world settled on 12-member juries requiring unanimity (or, in modern England and Wales, near-unanimity of 10 or 11), Scotland developed and retained a 15-member jury that could convict on a bare simple majority — as few as 8 votes for guilt. This made Scotland something of an outlier even among the UK's own constituent jurisdictions, let alone against the United States, Canada, Australia, or other common-law systems.

The precise origin of the number fifteen is not as cleanly documented as, say, the 2026 reform that changed the majority rule. The traditional account places the modern form of the Scottish jury system as settling into its recognisable shape over the 18th and 19th centuries, as Scotland's post-1707 legal system — preserved as a separate institution under the Treaty of Union — developed its own procedural conventions distinct from England's, drawing on a different mix of continental, canon-law-influenced, and indigenous Scottish legal tradition. By the time 20th-century statute came to consolidate criminal procedure, the 15-member jury and the simple-majority rule were treated as settled, taken-for-granted features of the system rather than live policy choices, surviving essentially unchanged through to the 1995 Criminal Procedure (Scotland) Act, which restated rather than reformed them.

The Doctrine Explained in Plain English

Historically, if you were on trial in Scotland's High Court of Justiciary or in the Sheriff Court under solemn procedure, your fate was decided by 15 ordinary citizens rather than the 12 familiar from television courtroom drama. And unlike England (where 10 of 12 jurors, or all 12, typically must agree) or the United States (where unanimity among 12 is usually required), the Scottish jury historically needed only a simple majority: 8 votes for guilty out of 15 was enough to convict, even though that meant 7 jurors could have voted not guilty or not proven. No formal unanimity, no "hung jury," and — crucially — no obligation for the jury to deliberate until they reached the maximum possible agreement; a bare majority sufficed.

This combination — a larger jury than most comparable systems, combined with a lower majority threshold than almost any of them — made Scotland historically distinctive in a way that was frequently cited by critics as unusually conviction-friendly, and by defenders as a sensible accommodation that spread decision-making responsibility across more citizens while avoiding the costs and delays of requiring unanimity (such as the "hung jury" retrials common in unanimity-based systems).

From 1 January 2026, this changed. The jury size remains 15, but the majority required to convict rose to at least two-thirds — meaning at least 10 of the 15 jurors must vote guilty. This brings Scotland's conviction threshold closer to, though still not identical to, systems requiring supermajorities or unanimity elsewhere, while preserving the larger jury size that remains Scotland's most visibly distinctive feature.

Key Reforms and the 2026 Change

The push to reform the jury majority rule did not happen in isolation. It emerged from a broader, years-long Scottish Government review of criminal justice and victims' experience of the system, closely linked to — but legally distinct from — the debate over abolishing the "not proven" verdict (covered in the companion card in this series) and the separate, ultimately abandoned, attempt to abolish corroboration in 2013–2015 (covered in its own companion card). A recurring theme across all of these reviews was the concern that Scotland's historic combination of three possible verdicts, a low conviction threshold, and no corroboration safeguard created a system whose different features interacted in ways that were hard to assess in isolation.

The Scottish Government's eventual package, legislated through the Victims, Witnesses, and Justice Reform (Scotland) Act and scrutinised by the Scottish Parliament's Criminal Justice Committee from 2024 onward, took a narrower path than the 2013–2015 corroboration reform attempt: it left corroboration untouched but combined abolition of the "not proven" verdict with a higher jury majority threshold, reasoning that removing one of the three verdict options without also tightening the majority rule could make wrongful conviction more likely, since jurors who might previously have returned "not proven" in a case of genuine doubt would, under a two-verdict system, be more likely to default to "guilty" on a bare majority. Raising the threshold to two-thirds was presented as a counterbalancing safeguard. This reasoning was contested throughout the legislative process: some victims' organisations argued it did not go far enough to improve conviction rates in cases such as rape and sexual assault, while significant parts of the legal profession warned the reform package as a whole risked unintended consequences that would only become apparent over time.

Present-Day Status and Ongoing Debate

As of October 2026, the two-thirds majority threshold and the abolition of "not proven" are both now in force for trials beginning on or after 1 January 2026, while the 15-member jury size remains unchanged. Legal commentators and academics continue to debate the likely practical effects: whether conviction rates for serious sexual offences will rise, fall, or stay broadly the same; whether the new threshold will produce more jury deadlock in practice (a phenomenon Scotland's old simple-majority system was largely designed to avoid); and whether further jury reform — including possible research into how 15-member juries actually deliberate, which the Act also provides for — will follow. Because the reform is so recent, robust empirical evidence of its real-world effects is not yet available, and any claim about its practical impact on conviction rates should be treated as prediction or early commentary rather than established fact.

• Scotland's 15-member jury means its juries are, numerically, 25% larger than the 12-member juries used in England, Wales, and most of the rest of the common-law world.
• Under the old simple-majority rule, a defendant could be convicted even if nearly half the jury — 7 of 15 — believed them not guilty or not proven.
• Scotland's jury system has traditionally had no formal concept of a "hung jury" in the way England or the United States does, because a simple majority (and now a two-thirds majority) can always, in principle, be reached without unanimity being required.
• The 2026 reform was legislated as part of the same Act that abolished the centuries-old "not proven" verdict — the two changes were deliberately bundled as a counterbalanced reform package rather than enacted separately.
• Mock-jury research commissioned by the Scottish Government has examined how 15-member Scottish juries actually deliberate, including whether the larger jury size changes group dynamics compared with 12-member juries — findings remain a live area of academic study.
• Scotland's historic simple-majority threshold (8 of 15, roughly 53%) was, proportionally, a lower bar for conviction than almost any other serious criminal jury system in the common-law world.
• The new two-thirds threshold (10 of 15) is still not full unanimity, meaning Scotland retains a materially different jury-verdict culture from unanimity-based systems even after the 2026 reform.
• No comparable reform has altered the actual size of the jury — commentary and reform proposals over the past decade have focused almost entirely on the majority threshold and verdict options, not on moving Scotland toward the more common 12-member model.

• Do not state that Scottish juries still convict by simple majority. Correct phrasing: This was true until 31 December 2025; from 1 January 2026, a two-thirds majority (at least 10 of 15 jurors) is required.
• Do not state that the jury size changed as part of the 2026 reforms. Correct phrasing: The jury remains 15 members; only the majority threshold changed.
• Do not state that there is a single, well-documented founding statute that created the number "fifteen." Correct phrasing: The 15-member jury is a long-settled feature of Scottish practice whose precise historical origin is less firmly documented than its long-standing application.
• Do not state as settled fact that the 2026 reform will reduce or increase wrongful convictions, or improve or worsen conviction rates for any offence category. Correct phrasing: These are contested predictions; robust post-reform evidence is not yet available given how recently the change took effect.
• Do not conflate the jury majority reform with the abolition of "not proven" as though they were the same legal change. Correct phrasing: They are two distinct provisions enacted in the same Act, taking effect on the same date — see the companion card on "Not Proven" for that specific topic.