1Ulpianus, On the Edict, Book XXXVI. The Prætor, through necessity, established an action to take the place of that of guardianship. For very often it is uncertain whether a party has administered the guardianship as an actual guardian, or merely as one occupying his place, and therefore he prescribed an action available in either instance; so that whether the guardian was an actual one who attended to the business, or whether he was not, he would still be liable to the action. For great uncertainty frequently arises, so that it cannot be easily ascertained whether he who administered the trust was really a guardian, or whether he was not, but merely performed the duties of the office in that capacity. 1A man transacts business as a guardian who discharges the duties of one with reference to the affairs of minors, either when he thinks himself to be a guardian, or knowing that he is not, nevertheless pretends to be one. 2Hence, if a slave acts in the capacity of guardian, the Divine Severus stated in a Rescript that an equitable action should be granted against his master on account of the acts of the slave. 3There is no doubt that an action can be brought against a party who transacted the business of a minor in the capacity of guardian, even before the latter arrives at puberty, for the reason that he is not really a guardian. 4Wherefore, if anyone acting as a guardian transacts the business of a minor after the termination of his guardianship, he will be liable. 5If anyone should administer a guardianship as a pretended guardian before his appointment, and afterwards as a real guardian, he will also be liable for acts performed while he was administering the trust without legal authority, although said acts will be included in an action on guardianship. 6Where anyone performs the duties of a guardian with reference to the affairs of a minor who has already reached the age of puberty and who therefore cannot have a guardian, an action of this kind will not lie. The same rule applies to the case of an unborn child, for where anyone acts as a guardian, it is necessary for the individual whom he represents to be of an age to have one, that is to say under the age of puberty. However, an action on the ground of voluntary agency will lie in this instance. 7Where a curator appointed for a minor by the Prætor transacts the business, the question arises whether he will be liable as one occupying the place of a guardian. The better opinion is that this action will not lie, because the party performed the duties of a curator. However, where there is no guardian, and someone is compelled, either by the Prætor or the Governor to act as such, and, believing himself to be a guardian, administers the guardianship, it should be ascertained whether he is responsible for his acts in the capacity of guardian. The better opinion is that he should still be liable, even though he acted under compulsion, for the reason that he transacted the business with the intention of a guardian, even though he was not one in reality. The above-mentioned curator, however, did not transact the business as a guardian but as a curator. 8In the action against a person who has acted as guardian interest is also included. 9Should the party who has acted in the capacity of guardian only be held liable for the business which he transacted, or also for that which he should have attended to? And, indeed, he will not be liable for anything which did not concern the guardianship, nor for any matter which should not have had connection with it, while he acted as guardian. Where he transacted certain business, it should be considered whether he can be held liable for what he did not attend to, and he will be responsible to the extent that another would have been if he had transacted it. But if, knowing that he was not a guardian, he refrained from administering the trust, let us see whether he can be held liable, if he did not notify the near relatives of the ward to have a guardian appointed for the latter. The better opinion is that he will be liable.

2Celsus, Digest, Book XXV. Where anyone transacts business as a guardian while he does not occupy the office, and sells property of the ward which is not subsequently acquired by usucaption; the latter can bring suit for said property even though security may have been given to him, for the reason that the administration of the affairs of a ward by a person acting as guardian is not the same as that of a real guardian.

3Javolenus, Epistles, Book V. I ask whether he who has been appointed a guardian by will, but is ignorant of the fact, can be held liable for attending to the business of the ward as an actual guardian, or for transacting said business as one acting in the capacity of a guardian. I answered that I do not think that he can be held liable as an actual guardian, because he must know that he is the guardian, in order to discharge the duties of the office with the same spirit with which a guardian should act.

4Pomponius, On Quintus Mucius, Book XVI. He who transacts business as an acting guardian should display the same good faith and diligence as a real guardian.

5Ulpianus, On the Edict, Book XXVIII. He who has transacted business while acting as guardian is entitled to the counter-action.