"x x x.
Finally, we find that a new trial based on newly discovered evidence is warranted. New trial is a remedy that seeks to “temper the severity of a judgment or prevent the failure of justice.” Thus, the Rules allows the courts to grant a new trial when there are errors of law or irregularities prejudicial to the substantial rights of the accused committed during the trial, or when there exists newly discovered evidence. The grant or denial of a new trial is, generally speaking, addressed to the sound discretion of the court which cannot be interfered with unless a clear abuse thereof is shown.
This Court has repeatedly held that before a new trial may be granted on the ground of newly discovered evidence, it must be shown (1) that the evidence was discovered after trial; (2) that such evidence could not have been discovered and produced at the trial even with the exercise of reasonable diligence; (3) that it is material, not merely cumulative, corroborative, or impeaching; and (4) the evidence is of such weight that it would probably change the judgment if admitted. If the alleged newly discovered evidence could have been very well presented during the trial with the exercise of reasonable diligence, the same cannot be considered newly discovered.
The only contentious element in the case is whether the evidence could have been discovered with the exercise of reasonable diligence. In Custodio v. Sandiganbayan, the Court expounded on the due diligence requirement, thus:
The threshold question in resolving a motion for new trial based on newly discovered evidence is whether the [proffered] evidence is in fact a “newly discovered evidence which could not have been discovered by due diligence.” The question of whether evidence is newly discovered has two aspects: a temporal one, i.e., when was the evidence discovered, and a predictive one, i.e., when should or could it have been discovered. It is to the latter that the requirement of due diligence has relevance. We have held that in order that a particular piece of evidence may be properly regarded as newly discovered to justify new trial, what is essential is not so much the time when the evidence offered first sprang into existence nor the time when it first came to the knowledge of the party now submitting it; what is essential is that the offering party had exercised reasonable diligence in seeking to locate such evidence before or during trial but had nonetheless failed to secure it.
The Rules do not give an exact definition of due diligence, and whether the movant has exercised due diligence depends upon the particular circumstances of each case. Nonetheless, it has been observed that the phrase is often equated with “reasonable promptness to avoid prejudice to the defendant.” In other words, the concept of due diligence has both a time component and a good faith component. The movant for a new trial must not only act in a timely fashion in gathering evidence in support of the motion; he must act reasonably and in good faith as well. Due diligence contemplates that the defendant acts reasonably and in good faith to obtain the evidence, in light of the totality of the circumstances and the facts known to him.
As previously stated, respondents relied in good faith on the veracity of the Order dated June 30, 1989 which petitioners presented in court. It was only practical for them to do so, if only to expedite the proceedings. Given this circumstance, we hold that respondents exercised reasonable diligence in obtaining the evidence. The certifications therefore qualify as newly discovered evidence.
The question of whether the certifications presented by respondents have any probative value is left to the judgment and discretion of the trial court which will be hearing the case anew.
x x x."