Supreme Court decides on Scottish minimum alcohol pricing
The UK's highest court will decide later whether Scotland can finally implement its policy of minimum pricing for alcohol.
Legislation was approved by the Scottish Parliament five years ago but it has been tied up in court challenges amid claims it breaches European law.
Ministers said a 50p-per-unit minimum would help tackle Scotland's "unhealthy relationship with drink".
The Supreme Court appeal was brought by the Scotch Whisky Association (SWA).
It said the policy was a "restriction on trade" and there were more effective ways of tackling alcohol misuse.
If the SWA appeal is dismissed, Scotland could become the first country in the world to establish a minimum price for alcohol - with ministers saying it would become law "as quickly as is practicable", possibly early next year.
How does minimum pricing work?
The Scottish government's aim is to reduce the amount that problem drinkers consume simply by raising the price of the strongest, cheapest alcohol.
The move is not a tax or duty increase. It is a price hike for the cheapest drink, with any extra cash going to the retailer.
Last year, Alcohol Focus Scotland claimed the maximum recommended weekly intake of alcohol (14 units) could be bought for just £2.52.
It said super-strength cider and own-brand vodka and whisky could be purchased for as little as 18p per unit of alcohol.
The 50p-per-unit minimum outlined by the legislation would raise the price of the cheapest bottle of red wine (9.4 units of alcohol) to £4.70, a four-pack of 500ml cans of 4% lager would cost at least £4 and a 70cl bottle of whisky could not be sold for less than £14.
Bottle of whisky
Strength 40% ABV
Units of alcohol 28
Bottle of Vodka
Strength 37.5% ABV
Units of alcohol 26.25
Bottle of White wine
Strength 11.5% ABV
Units of alcohol 8.625
Bottle of red wine
Strength 12.5% ABV
Units of alcohol 9.375
Bottle of cider (normal strength)
Strength 5% ABV
Volume 1 litre
Units of alcohol 5
Four cans of lager
Strength 4% ABV
Volume (4x440 ml) 1.76 litres
Units of alcohol 7.04
Big bottle of alcopops
Strength 4% ABV
Units of alcohol 2.8
Off-sales and supermarkets
Minimum pricing will not raise the prices of all alcoholic drinks because many are already above the threshold.
Pubs and bars are unlikely to be affected as they usually charge much more than 50p per unit.
The aim is to hit consumption of strong alcohol which is sold at low prices.
The new laws would be "experimental" and expire after six years unless renewed.
Scotland's Health Secretary Shona Robison said: "Alcohol is 60% more affordable in the UK than it was in 1980 and alcohol misuse costs Scotland £3.6bn each year - £900 for every adult.
"There is strong evidence that tackling price helps reduce consumption and related harm."
During a two-day hearing at the Supreme Court in July, the QC for the Scotch Whisky Association said the case could set a far-reaching precedent and have an impact on international trade.
He said the nub of the SWA argument was "why not tax?".
The lawyer said that to discriminate against products because they are cheap went against "the absolute fundamentals of the free market".
Timeline: Minimum pricing for alcohol
The latest phase of the five-year legal battle will be decided in London, having already passed through courts in Edinburgh and Luxembourg. After an initial challenge at the Court of Session failed in 2013, the SWA appealed to the European Court of Justice (ECJ).
The European court said the legislation might break EU law if other tax options would prove as effective, but said it was "ultimately for the national court to determine" whether they did.
The Scottish court subsequently backed the measures for a second time, ruling that tax measures "would be less effective than minimum pricing".
However, in December 2016 the Court of Session judges then allowed the SWA to go to the Supreme Court to challenge their ruling.
May 2012: MSPs pass Scots booze price plan
May 2013: Minimum drink price challenge fails
December 2015: Minimum drink price 'may breach EU law'
October 2016: Courts back minimum alcohol price
December 2016: Whisky firms allowed minimum price appeal
What's the situation elsewhere in the UK?
The UK government supported the devolved Scottish administration during the legal process, arguing that minimum pricing was compatible with EU law.
In 2012, then Prime Minister David Cameron pledged to introduce minimum pricing - but the plan was shelved a year later in the face of fierce opposition from the drinks industry.
The Home Office has said the policy remains under review, with calls for its reintroduction in England likely to be reignited if it is eventually implemented in Scotland.
Legislation to establish a minimum price is currently under active consideration by the National Assembly for Wales and by the Irish Seanad (the upper house of the Irish parliament).
In Northern Ireland, former Health Minister Jim Wells had been seeking to introduce minimum pricing before resigning in April 2015.