Banking Fraud

When a bank judicially demands payment of an obligation that has been fully or partially extinguished, this constitutes a defect that can lead to the complete dismissal of the enforcement action. In these cases, the debtor can raise the defense of payment, submitting bank documentation, account statements, receipts, or renegotiation records that prove the debt was extinguished. If the bank sued without checking its internal records or presented contradictory information, this can result in an award of costs against it and, potentially, civil liability if the collection caused additional harm, such as improper attachments, damage to the debtor’s credit standing, or moral damages arising from negligent conduct.

Contract clauses that attempt to shift all liability onto the customer are usually reviewed under the standard of care required of financial institutions, which must ensure robust authentication systems, transaction monitoring, and adequate security controls. Consequently, not every instance of unauthorized access can be attributed to the user; to be released from liability, the bank must show that its infrastructure operated within reasonable parameters and that the customer’s conduct amounts to gross negligence. Courts have consistently held that merely invoking general “duty of care” clauses is insufficient, requiring a specific assessment of the incident. For that reason, the automatic rejection of a claim does not mean the right to challenge it in court is lost.

When the instrument relied upon contains clauses that violate Law 19,496 (Ley 19.496) or financial system regulations, the debtor can challenge the validity of the obligation through the defense of nullity or lack of executive force. Courts examine whether the interest charged complies with the legal limits (including the maximum conventional rates) and whether the clauses meet the requirements of transparency and contractual balance. Where overcharges, improper ancillary charges, or mechanisms that undermine the customer’s valid consent are detected, the enforcement action can be dismissed or the debt recalculated. The bank must prove the legitimacy of the charge, and the burden of proof cannot be automatically shifted onto the consumer.

The first thing is to dispute the transaction with the bank or issuer through a means that leaves a record, immediately upon detecting it. Law No. 20,009 (Ley N° 20.009) governs liability for fraudulent transactions with means of payment and limits the holder’s liability when they have given timely notice; the issuer must refund the disputed amounts within the legal deadlines, unless it proves willful misconduct or gross negligence by the user. Keep the receipts, the complaint or ticket number, and all communications with the bank. If the bank refuses the refund without grounds, there are avenues for complaint before the National Consumer Service (SERNAC) and the courts.

As a general rule, yes. Under Law No. 20,009 (Ley N° 20.009), once the user gives notice disputing a transaction, the issuer must cancel or refund the disputed amounts within the deadlines set by law, and may only withhold or charge them if it proves that there was willful misconduct or gross negligence by the holder. It is not enough for the bank to claim that the passwords were used: the burden of proving the customer’s improper conduct falls on the institution. If the bank refuses to refund without proving those circumstances, you can file a complaint and sue for restitution, in addition to any corresponding compensation.

The essential thing is to notify the bank as soon as you detect the fraudulent transaction, since timely notice triggers the protection of Law No. 20,009 (Ley N° 20.009) and limits your liability. Beyond that immediate notice, you retain the right to claim restitution and, where appropriate, to sue for compensation, within the applicable prescription periods. It is advisable not to let time pass: review your account statements periodically, immediately dispute anything you do not recognize, and keep the record of the notice. If the bank does not respond or rejects the claim, you can turn to the National Consumer Service (SERNAC) and the courts to demand the refund.