The Civil Procedure Act regulates the rules on proof concerning contract law. Besides these articles in the Civil Procedure Act, there are general principles: the plaintiff has the burden of proof of his claim (wie stelt, bewijst) and the defendant needs to proof the defenses (onderbouwing). These general principles correspond with the Dutch general principles of burden of proof.
Applying these principles specific on contracts and the circumstance where breach of contract arises, the plaintiff has the burden of proof of existence of the contract and its breach. Concerning the juridical questions of accountability or proof of fault (toerekenbaarheid), Spanish case law (in tort liability and professional liability) is ambivalent. Proof of burden may shift to the defendant.
Furthermore, case law holds two duties. I refer with this term to the obligation do something. The duties are not codified in the civil code. These duties are of duty of best efforts and duty to achieve a specific result. In some cases liability can be escaped when is shown that obligations are performed diligently.
Contracts need to be drafted custom fit to prevent problems or unwanted situations during the executing. When disputes arise, legal filling is essential. Clear juridical correspondence in which your position comes strongly is fundamental.
If you need advise or support with legal administration, correspondence and filling, don’t hesitate to contact me.