Halliday & Matthiessen (1999: 250-2):
Here a figure is being construed metaphorically on the model of a participant: grammatically, the figure is construed not as a clause but as a nominal group. There is a shift in rank from figure to element, and concomitantly a shift in status among the elements making up the construction.
he was arrested by the police => his arrest by the police
(…) bond rapidly => rapid bonding occurs
the group decided yesterday => yesterday’s decision by the group
the accused appeared to be innocent => the apparent innocence of the accused
he argues cogently => the cogency of his argument