A plea from Scotland's most senior judge for Westminster to give Scottish courts the same rights as those in the rest of the UK has been rejected.

Lord Hamilton, the Lord President, yesterday effectively backed First Minister Alex Salmond and the SNP in their judicial turf war with the UK Supreme Court.

Echoing senior prosecutors and ministers, the veteran lawman called for the London court to treat Scottish criminal appeals in exactly the same way as those from England, Wales and Northern Ireland.

Lord Hamilton's intervention, however, last night appeared to have fallen on deaf ears at Westminster as Lord Wallace, the Advocate General for Scotland, signalled he "remained to be persuaded".

Leading QC Paul McBride said Lord Wallace's stance effectively meant Britain had two classes of judges. He said: "Basically, we have English judges who can be trusted and Scottish ones who can't."

Lord Hamilton and the Holyrood ministers' complaint stems from the UK Supreme Court's 2010 "Cadder" decision, which gave suspects in custody the right to legal advice.

Privately, Scottish judges were known to have been left distraught by the judgment, which overturned a decision by the most senior legal minds north of the Border and sparked chaos throughout the justice system.

However, it was broadly welcomed by defence and human rights lawyers, who believed Scots Law needed fundamental reforms that senior judges such as Lord Hamilton were not prepared to support.

The Supreme Court was able to make "human rights" judgments on Cadder, but would not have been able to do so with a matter from a court elsewhere in the UK without being asked to do so by its judge.

Lord Hamilton, acting on behalf of the entire Scottish judiciary, yesterday formally asked the UK Parliament to use the current Scotland Bill to change that rule.

He said: "The Lord President is urging Parliament to do two things: to extend the jurisdiction of the Supreme Court in Scottish criminal appeals and references to the remedying of infringements by the courts below as well as by the prosecutor; but to restrict those cases in which leave may be granted to appeal to the Supreme Court from the High Court of Justiciary to cases in which the High Court has certified that a point of law of general public importance is involved in the decision."

Lord Wallace, in a letter to Scottish Justice Secretary Kenny MacAskill seen by The Herald, rejected that view.

He wrote: "I remain to be persuaded that it is necessary to require an appeal under the new appeals route to be certified by the High Court before it can be appealed to the Supreme Court."

Historically, the High Court of Justiciary was the court of final appeal in all Scottish criminal cases.

However, the UK Supreme Court started to review "human rights" aspects of such appeals – rather than the evidential merits of cases – after it was set up in 2009.

This sparked two major controversies, first Cadder and then last year's decision to quash the high-profile 1998 murder conviction of Nat Fraser, who is now facing a retrial.

Mr Salmond last year accused one of the UK Supreme Court justices, Scot Lord Hope, of trying to overturn centuries of independent Scottish jurisprudence.

He said: "It boils down to the potential replacement of Scottish law by Lord Hope's law. I don't think that's a satisfactory situation."

Those remarks – and threats by Justice Secretary Kenny MacAskill to cut funding to the UK Supreme Court – sparked fury among many lawyers and human rights campaigners.

Mr McBride said Mr Wallace had made a "frankly disgraceful political decision" that would fuel nationalist sentiments.

He said: "We have a position whereby our Scottish courts who say 'no' can be overruled by judges in England, whereas if the English courts say 'no' they can't be overruled by the Supreme Court in England.

"It is for these very reasons that support for the union is haemorrhaging."

A Scottish Government spokeswoman said: "We welcome the Lord President's intervention, which underlines the seriousness with which the matter is being treated by the Scottish judiciary, and support his view.

"We agree that the High Court of Justiciary should have the final say on which points of law are of general public importance and with the recommendation of a certification process."

Human rights specialist John Scott QC last night disputed claims current arrangements meant Scottish courts were second class.