1. Historically, there were three torts in relation to goods: conversion, trespass to goods, and detenue.
The Torts (Interference with Goods) Act 1977 reduced that to conversion and trespass to goods.

2. Conversion ( = negligent appropriation)
a) It is committed when a person deals with the goods of another in such a way as to show that he calls the title of the owner in question. This includes the wilful taking of another person's goods, the re-selling of goods innocently ac- quired: Hollins v. Fowler 1875 - goods obtained by fraud were re-sold by yet another (H); he was guilty of conversion even though he was ignorant of F's rights (negligence will suffice).
b) The person entitled to claim is the person in possession of the goods or the person who, though not in possession, is entitled to the immediate possession of them at the time of the wrong.
aa) Therefore, anyone in possession can claim:
Armory v. Delamirie 1722 - a finder claiming against one whom he had entrusted the gem found.
bb) By contrast, the owner may not be entitled to sue if he is not entitled to the immediate possession of the goods.

3. Trespass to goods ( = strict; just moving)
a) This is direct interference with goods in the possession of another (who is then entitled to sue).
b) The interference need not be physical (though it usually is) - as where cattle is driven away.
c) No converting (assuming title) nor negligence is required: Bushell v. Miller 1718 - a man who merely removed goods (and forgot to put them back) was liable for the mere act act removing them.

4. Contributory negligence is no defence (under the Act) to a claim in conversion or for intentional interference with goods.