Were They An Inmate?
Institutions such as workhouses, prisons and asylums were obliged to enumerate their occupants, but they were often only differentiated by initials (especially in prisons). Clues such as occupation and place of birth should still be there though. If you find a likely candidate then you will need to look into the records of the institution in question. If you think someone may have fallen foul of the law – or just fallen on hard times – then try searching with just initials and place of birth (and, if using thegenealogist. co.uk, occupation as well).