The process by which this came to pass has been traced above, but a few words may be added here.  The Year Books, even in dealing with the destruction (as distinguished from the conversion) of chattels in the hands of a bailee, always state his liability as based upon his fault, although it must be admitted that the language is used alio intuitu. 2 A jettison, in tempest, seems to have been a good plea for a factor in the time of Edward III.; 3 but that cannot be relied on for an analogy.  The argument from the Marshal’s case 4 is stronger.  There it appears to have been thought that burning of the prison was as good an excuse for an escape as a release by alien enemies.  This must refer to an accidental fire, and would seem to imply that he was not liable in that event, if not in fault.  The writs in the Register against bailees to keep or carry goods, all have the general allegation of negligence, and so do the older precedents of declarations, so far as I have observed, whether stating the custom of the realm or not. 5 But a bailee was answerable for goods wrongfully taken from him, as an innkeeper was for goods stolen from his inn, irrespective of negligence. 6

It is true that the Marshal’s case speaks of his negligent [201] keeping when the prisoners were released by rebels, (although that was far less likely to result from negligence, one would think, than a fire in the prison,) and that after Lord Coke’s time negligence was alleged, although the goods had been lost by wrongful taking.  So the writ against innkeepers is pro defectu hujusmodi hospitatorum.  In these instances, neglect only means a failure de facto to keep safely.  As was said at a much later date, “everything is a negligence in a carrier or hoyman that the law does not excuse.” 1 The allegation is simply the usual allegation of actions on the case, and seems to have extended itself from the earlier declarations for damage, when case supplanted detinue and the use of the former action became universal.  It can hardly have been immaterial to the case for which it was first introduced.  But the short reason for disbelieving that there was any warrant in the old law for making the carrier an insurer against damage is, that there seem to be no early cases in which bailees were held to such a responsibility, and that it was not within the principle on which they were made answerable for a loss by theft.

Having traced the process by which a common carrier has been made an insurer, it only remains to say a word upon the origin of the admitted exceptions from the risk assumed.  It has been seen already how loss by the public enemy came to be mentioned by Chief Justice Holt.  It is the old distinction taken in the Marshal’s case that there the bailee has no remedy over.