I shouldn't be at all surprised if Elizabeth Scarborough (not a writer whose work I know) got the idea from a ballad like  Young Benjie  or something similar; what she seems to have done is confuse the lyke wake (a perfectly normal custom) mentioned in the song with the quite separate folk-belief, also mentioned, to the effect that under certain circumstances it might be possible to identify a murderer through observing the corpse; in this case at midnight on the eve of burial the corpse was able, briefly, to speak.  It was also commonly believed that the wounds on a corpse would begin to bleed afresh in the presence of the murderer, or that the eyes retained the last image seen before death, and could be examined for evidence.  Interesting stuff; unfortunately I must go back to work now, sigh...

Malcolm