“…about their legal consequences would not amount to a defence: Greig v Insole [1978] 1 WLR 302; Pritchard v Briggs [1980] Ch 338 (Goff LJ). The latter case was a case of conspiracy to injure by unlawful means. But in Mainstream Properties Ltd v Young [2005] EWCA Civ 861, [2005] IRLR 964 …”
“… the defendant knew the facts, then a mistake about their legal consequences would not amount to a defence: Greig v Insole [1978] 1 WLR 302; Pritchard v Briggs [1980] Ch 338 (Goff LJ). But in Mainstream in this court Arden LJ specifically disagreed with that view on the basis that the law about mistakes of law had moved on. In Main…”