A heartening, very interesting - and highly unusual - intervention by the Lord Advocate:
Scotland's top prosecutor has said the case has not been made for extending the length of time terror suspects can be detained without charge to 42 days.
BBC Scotland has learnt that Lord Advocate Elish Angiolini gave her opinion in a letter to the Liberal Democrat MP Alistair Carmichael.
She said the change from the current 28 days was not supported by "prosecution experience to date"...
"While there has been a limited number of cases in Scotland which were investigated in terms of the Terrorism Act 2000, I am not aware of any case where an extension of the period beyond 28 days would have been required.
"I therefore share the view of the DPP (Director of public prosecutions) Sir Ken MacDonald and the former Attorney General, Lord Goldsmith, that the requirement for an extension to the current 28 day is not supported by prosecution experience to date."
Will this help? One can but hope so. Ministers are briefing that the vote is "tight" at present. My guess is, alas, that the government will prevail.