There are two types of criminal procedure - solemn and summary.
A solemn procedure trial in both the High Court and the Sheriff Court is held before a judge sitting with a jury of 15 people.
In summary procedure, a trial is held in Sheriff or Justice of the Peace Courts before a judge without a jury.
The Lord Advocate or her local representative, the Procurator Fiscal, prosecutes cases in each criminal court on behalf of the public. The police do not prosecute and private individuals can only prosecute in very rare circumstances.
Solemn procedure covers the most serious cases. It involves trial on indictment before a judge or sheriff sitting with a jury. A Scottish jury is made up of 15 people and a simple majority (8-7) is sufficient to establish guilt or innocence. Three verdicts are available to the jury: guilty, not guilty, or not proven.
A not proven verdict is the equivalent of not guilty in that it is an acquittal. Criminal Justice and Parole Division deals with policy on solemn criminal procedure matters and took forward the passing and implementation of the Criminal Procedure (Amendment) (Scotland) Act 2004 - which reformed the operation of the solemn courts. Further work is currently underway to reform sheriff and jury procedure.
That 2004 Act originated from Lord Bonomy's report Improving Practice - The 2002 Review Of The Practices And Procedure Of The High Court Of Justiciary.
Further information on the reform of sheriff and jury procedure can be found here.
Summary procedure covers less serious cases involving a trial where there is no jury - either a sheriff sitting alone, a stipendiary magistrate sitting alone, a justice of the peace sitting alone, or a bench of 3 justices of the peace sitting together.
Criminal Justice and Parole Division also has policy responsibility for summary criminal procedure and they led a programme of summary justice reforms, which were implemented using provisions contained in the Criminal Proceedings etc. (Reform) (Scotland) Act 2007.