Imprisonment wasn't really an option at the time. Transportation or death were the normal sentences for all but minor felonies. Many death sentences were commuted to transportation or even pardoned. You often find that those sentenced to transportation were previously sentenced to whipping and or short sentences previously
James's own testimony would have been used fill in his age; he may not have known his exact age.
I haven't checked my notes (so from memory), in a recent lecture by Dr Rosalind Crone ( creator of this prison database. ) she said that research suggests that prisoner description information recorded by gaolers was 'accurate' in that very similar info was recorded on subsequent admissions, even to different establishments.
