Test on whether amendment prejudicial to the accused

The test as to when the rights of an accused are prejudiced by the amendment of a Complaint or Information is when a defense under the Complaint or Information, as it originally stood, would no longer be available after the amendment is made, and when any evidence the accused might have, would be inapplicable to the Complaint or Information as amended. On the other hand, an amendment which merely states with additional precision something which is already contained in the original information, and which, therefore, adds nothing essential for conviction for the crime charged is an amendment to form that can be made at any time. (Gahionza v. Court of Appeals, 408 Phil. 58, 64-65, year 2001)