Scotland's top law officer has said that the courts should be able to impose sentences of longer than 30 years for those found guilty of murder.

Lord Advocate Elish Angiolini told the Court of Criminal Appeal that the current scale of between 12 and 30 years for murder is inadequate and that, in the most serious of cases, life should mean life.

Over the next four days, Mrs Angiolini will argue before Appeal Court judges that there should be a review of sentencing in murder cases and that 30 years should not be the maximum guideline.

Robert Kelly strangled grandmother Agnes Mechan to death and hid her body under floorboards. After pleading guilty his sentence was reduced from 20 to 15 years.

Brian Boyle and Greig Maddock beat father of two Brian Bowie to within an inch of his life and set him on fire. He died five days later. Boyle was sentenced to a minimum of 15 years, Maddock ordered to serve at least 12.

Mrs Angiolini has condemned the sentences in both cases as unduly lenient. In her opening remarks, the Lord Advocate used the law in England and Wales as an example where a punishment of a 'whole of life’ sentence is available.

She asked the Appeal Court to consider that there are some cases where a sentence which exceeded the natural life expectancy of the accused may be appropriate.

She said: "I asked the court to reflect on the number of knives, and in particular swords, carried in Scotland and used as weapons, often against passers-by whose lives are viewed by their assailants as nothing more than a cheap commodity."

Appeal judges will also be asked by the Crown Office to consider the appropriate level of discount given for a guilty plea, with Mrs Angiolini seeking assurances that it is not inflated in cases of a determinate sentence.

Scots Law expert James Chalmers also believes the whole life sentence option should be considered. He said: “In England we’ve had a small number of people where a whole life tariff has been imposed and, in principle, that’s the kind of power that probably ought to be open to the Scottish courts. Although, ideally, that would be decided by parliament – not by the courts themselves.”

STV's Political Editor Bernard Ponsonby gives his analysis of the Lord Advocate's comments here.