G.R. No. L-10868; August 28, 1916
LEOCADIO JOAQUIN, plaintiff-appellant, vs. O. MITSUMINE, defendant-appellee.

FACTS:
Plaintiff Leocadio Joaquin, an attorney, filed a complaint seeking the annulment of a chattel mortgage he executed on July 3, 1914, in favor of defendant O. Mitsumine. The mortgage secured two promissory notes totaling P525, representing the unpaid balance for a “Suchiro” aerated-water machine imported from Japan. Joaquin alleged the mortgage was executed by mistake, claiming he ordered the machine in May 1914 on behalf of his client, Macario Vito, and that Vito was solely responsible for payment. Mitsumine refused to cancel the mortgage. The trial court upheld the mortgage’s validity, absolved Mitsumine, ordered Joaquin to pay the debt plus collection expenses, dissolved a preliminary injunction against foreclosure, and taxed costs against Joaquin. Joaquin appealed.

ISSUE:
Whether the chattel mortgage executed by Leocadio Joaquin is null and void on the ground that it was executed by mistake, as he allegedly acted only as an agent for his client, Macario Vito.

RULING:
The Supreme Court AFFIRMED the trial court’s judgment. The chattel mortgage is VALID and BINDING upon Leocadio Joaquin.

The Court found that Joaquin, in his own name and for his own account, ordered the machine from Mitsumine on April 15, 1914. He made partial payments totaling P200, executed the promissory notes for the balance, and secured them with the chattel mortgage on the machine. The evidence showed Mitsumine did not know Macario Vito and had no contract with him. Joaquin, by his own acts, induced Mitsumine to believe he was the real purchaser. Consequently, Joaquin is estopped under the Code of Civil Procedure from denying his role as the principal obligor.

The Court applied the general principle that a party cannot contradict his own acts to the prejudice of another who relied upon them. The validity of obligations in authentic documents (like the mortgage and promissory notes) cannot be overthrown by the self-serving testimony of the obligor. To annul a contract for mistake, the conditions under the Civil Code must be strictly met, which Joaquin failed to prove. As an attorney, he could not plausibly claim ignorance of the contracts he willingly signed.

The appeal was deemed unwarranted. The trial court’s judgment was affirmed, with double costs against appellant Joaquin.