Mr MacAskill wrote to Justice Secretary Keith Brown seeking clarity on the issue. “No one denies that there’s a serious problem with delays in serious criminal trials,” MacAskill said.

“But other options to address delay are available, likewise with low conviction rates in sexual offences. This strikes at the heart of the justice system and is a step too far. Especially from a government where lines have been crossed in the separation of the role of the lord advocate and where there’s been little alacrity shown to separate the post of senior government law officer from that of the country’s most senior prosecutor.”

Lord Advocate Dorothy Bain QC has said politicians are “morally obliged” to consider juryless trials in order to address the mounting backlog of criminal cases.

The Scottish government said: “We will hold a consultation on sexual offences and victim rights in the spring, which will also cover many of the recommendations. Any decision on the way forward, and which would require legislation, will rightly be a matter for the Scottish Parliament.”