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[1946] KB 393 (CA). Harper v charlesworth (1825) confirmed that the right to sue for trespass to land was consequent on being in possession of the land, rather than having an Estate in land. In Delaney the claimant, who was essentially a squatter, sought to rely on this principle to prevent his eviction by a houseowner (in fact, the claimant had been given permission to move in, but not in writing). The Court held that mere possession of land did not give title to sue the person who owned the freehold interest in trespass.