It works by heating the moisture in a person's skin to the point where it feels, according to Kelley Hughes, an official at the directorate who volunteered to act as a guinea pig, like opening a hot oven.

ECONOMIST: Electromagnetic weapons

The sheriff also said it was agreed that Bryceland was not detainable in terms of the Mental Health Act during the period leading up to Ms Hughes' death and that as a voluntary patient it was his decision what help to accept and whether or not to take his medication.

BBC: 'No fault' in insane killer James Bryceland case

And it brings to mind a highly controversial piece of economic work by Professors Andrew Hughes-Hallett and Drew Scott, published last year, which argued that the act of devolving tax power in itself can drive up growth rates, at least temporarily.

BBC: Tax Cuts Earn Limited Returns