149. Any agreement which involves the doing of an act which is positively forbidden by law, or, what amounts to the same thing, the omission to do an act which is positively enjoined by law, is illegal and void. Acts may be so prohibited or enjoined

(a) By the rules of the common law; or

(b) By statute.

There are many acts which the law positively forbids or enjoins, and to the doing or omission of which some penalty is attached.

1 Edgar Lumber Co. v. Cornie Stave Co., 05 Ark. 449, 130 S. W. 452; Piper v. Boston & M. R. It., 75 N. H. 435, 75 Atl. 1041; Crigler v. Shepler, 101 Pac. 619, 23 L. R. A. (N. S.) 500, 79 Kan. 834. See "Contracts," Dec. Dig. (Key-No.) § 103; Cent. Dip. §§ 468-476.

2 Pol. Cont (3d Ed.) 251.

Whether the prohibition or injunction is by the common law or by statute is altogether immaterial. So it does not matter whether the act to be performed is malum in se or malum prohibitum.8 The act or omission prohibited may be some grievous crime, such as murder; or it may be an act or omission prohibited merely as a police regulation, as in the case of statutes regulating the conduct of a particular trade or business, with only a small fine as the penalty; or again it may be only a civil wrong. All of these cases stand on the same footing. If the subject-matter or object of an agreement is such that its performance would consist in an act or omission so forbidden, or be, so connected therewith as to be in substance part of the same transaction, the courts will not enforce it.

Same - Breach Of Rules Of Common Law

150. The agreements which are illegal because they are in breach of rules of the common law are:

(a) Agreements involving the commission of crime; and

(b) Agreements involving the commission of a civil wrong.

This classification, like that in the preceding section, is, from the nature of the subject, only approximate, and for convenience in treatment. Many acts are prohibited by statute which were formerly prohibited by the common law, and many acts which are prohibited by the common law in one state are prohibited by statute in another, and in some states there are no common-law crimes at all. For this reason, in treating of agreements in breach of rules of the common law we must include agreements in breach of statutes which are merely declaratory of the common law.