The Same, Opinions, Book IV. It is entirely proper to advance the expenses of a suit to a party engaged in litigation, but it is not legal to enter into an agreement that the sum expended for that purpose shall not be paid with lawful interest, but that half the amount recovered by the suit shall be paid.

Ulpianus, Opinions, Book IV. An official who acts for a city cannot transact public business through an agent.

The Same, Opinions, Book IV. Where an expenditure of money is advantageously made by some one while transacting the business of another, which includes expenses honorably incurred to secure public offices which are obtained by degrees; the sum expended can be recovered by an action based on business transacted. 1Where slaves have received their freedom absolutely by will, they are not compelled to give an account of the matters which they transacted during the lifetime of their master. 2Titius, being under the impression that his sister was the testamentary heir of the deceased, paid a debt to the creditors of the estate. Although he did this with the intention of transacting the business of his sister, he was in fact doing it for the children of the deceased who would be the proper heirs of their father if there had been no will; and, because it is just that he should not be subjected to loss, it is established that he can recover what he has paid by a suit based on business transacted.

Ulpianus, Opinions, Book IV. When a competent judge is informed by an innocent man that he has paid money on account of a crime which was not proved against him; he must order what has been unlawfully extorted to be refunded, according to the terms of the Edict which treat of persons who are said to have received money either to cause annoyance, or to refrain from doing so; and he must inflict punishment in proportion to the crime upon the party who committed it.

Ulpianus, Opinions, Book IV. A certain man was the possessor of an article which he wished to sell, and another brought suit to establish the right of property, and after having deprived him of the opportunity of selling the article to the purchaser, he abandoned the case. It was held that the party in possession was under the circumstances entitled to an action in factum for the purpose of indemnification.

Ulpianus, Opinions, Book IV. Unlawful assembles must not be attempted, even by veteran soldiers, under the pretext of religion, or that of performing a vow.