By Peter Lockhart of the Law Society of Scotland's Criminal Law Committee.
The decision by the Supreme Court to uphold the appeal in Cadder v Her Majesty's Advocate will have profound implications on Scots Criminal Law for many years.
As a busy criminal law practitioner with more than 30 years experience, it will change the way we do things here in Scotland forever. Has it come as a surprise?
Not really. Clearly the lord advocate saw the writing on the wall when interim guidelines were introduced in the summer on the matter.
Today it is important to look to the future, rather than dwell on the past.
How will this affect us in the coming weeks, months and years?
Firstly we will have to have regard to the emergency legislation the Scottish government proposes to introduce within the next few days.
That effectively will mean a suspect will be entitled to legal advice and, if necessary, a solicitor present during interview, where they have been detained.
In addition, the six-hour limit becomes 12, with an additional 12 hours in certain defined circumstances upon the authorisation of the custody review officer.
The legal profession are concerned at this.
Nevertheless, let's hope anything over six hours will be the exception not the norm.
Potentially, we could be on call 24/7.
There were initial concerns about that in the summer but in practice it appears to be working reasonably well.
Changes to the Legal Aid system are to be welcomed, although the grants of legal aid will have to be properly resourced.
However, it will be some time before satisfactory working arrangements are in place throughout the length and breadth of Scotland.
There will be particular difficulties in some of the more remote Highland and Island communities.
There are concerns whether many police stations have the facilities to detain people for longer periods.
All those within the Criminal Justice System must work together, to ensure the law strikes the appropriate balance between fairness to a suspect and the interests of justice.
Of more immediate concern to criminal practitioners will be the number of cases affected by today's ruling.
At our local court, numerous cases have been "parked" over the past few months awaiting this decision.
What will happen to these cases?
Presumably the Crown Office will have to take a decision on whether to continue with the prosecution.
This may mean some accused will find proceedings being dropped against them.
It is impossible to determine the numbers involved.
The decision makes it clear closed cases will not be affected by today's decision.
However, at the end of the day, the law in Scotland is clear on this issue, accordingly provision will have to be made.
On a positive note, all those within the Scottish Criminal Justice System, will continue to work together.
One thing is for sure, things will never be quite the same again here in Scotland for criminal practitioners.
Peter M S Lockhart is a criminal defence lawyer in Ayr. He is Dean of Ayr Faculty of Solicitors and a member of the Law Society of Scotland's Criminal Law Committee.