6. Because the Crown is a legal person at common law, in principle statutory authority is not needed before the Crown can make a contract. The Crown will however be bound by statutory provisions which expressly bind the Crown or which, by necessary implication, do so. For example the effect of statutory provisions may be to limit the purposes for which a power may be exercised or specify the manner in which a power is to be exercised or limit the extent to which a power can be devolved. Each case therefore needs to be considered against any relevant statutory provisions to determine whether the Crown is acting within them.
7. It is likely that the Crown cannot be prevented by an existing contract from exercising powers which are vested in it either by statute or common law, but this is unlikely to have an impact on commercial contracts (see generally Bradley and Ewing Constitutional and Administrative Law 12th Edition at pages 846 & 847).
8. Payments by the Crown require the statutory authority of an annual appropriation by Parliament in an Appropriation Act and no Parliament is able to bind its successors, or even itself, to vote money in future years. The Government presents estimates to Parliament for approval, in order that obligations entered into under contract can be fulfilled out of money voted by Parliament.
9. The effect of sections 1 and 2 of the Crown Proceedings Act 1947 is that the Crown can be sued in contract and tort. Procedurally this is done by claiming against the appropriate Government department listed under section 17 of the Crown Proceedings Act. Where there is no relevant department listed or where it is unclear which department to claim against, claims can be brought against the Attorney General. This generally places the Crown in the same position as any contracting party, but there are some privileges and immunities which the Crown Proceedings Act has preserved. Section 21 provides that courts have no power to grant an injunction or to make an order of specific performance - instead the court may make an order declaratory of the rights of the parties. However this provision is modified in relation to procurement to enable the courts to suspend the procedure leading to award of the contract. The Crown is immune from the usual methods of enforcing a judgment against it - the department is however required by section 25 of the Act to pay the amount certified by the court to be due as damages and costs.
10. Subject to what is said above, the ordinary rules of contract apply to the Crown. In addition, it is a principle of constitutional law that a decision made on a Minister's behalf by one of his officials is that of the Minister. The official acts as the Minister himself or herself and the official's decision is that of the Minister. This is known as the Carltona principle after the case of Carltona Ltd v. Commissioners of Works [1943] 2 All ER 560: see also R v. Skinner [1968] 2 QBD 700 at 707 . Except where the express delegation of authority is required by a particular statute, the civil servant's authority flows from the general nature of his or her administrative work and not from formal delegation.