ALEX JACOBO y SEMENTELA, petitioner, vs. COURT OF APPEALS and PEOPLE OF THEPHILIPPINES, respondents.[G.R. No. 107!!.Ma"#$ %1, 1!!7&Self-defenseinaprosecutionfor homicideshiftstheburdenof proof totheappellant. Havingadmitted the killing, the accused must prove by convincing evidence the various elements of his chosendefense. Onappeal,thisburden becomes even more difficultaspetitioner must showthat thecourtsbelowcommitted reversible error in appreciating the evidence and the facts, for basicis the rule thatfactual findings of trial courts, when affirmed by the appellate court, are binding upon the Supreme Court.Where two persons agree to fight, there is no unlawful aggression where there is no unlawful aggression,there can be no self-defense.!acts""That on or about April 14, 1987, in the City of Manila, Philippines, the said accused did then and there willfullysic!, unlawfully and feloniously, with intent to "ill, attac", assault and use personal #iolence upon one $%M&% '&(&)*) + MAT&%, by then and there stabbin, hi- with a "nife on the different parts of the body, thereby inflictin,upon the latter -ortal wounds which were the direct and i--ediate cause of his death.#pon arraignment, petitioner pleaded not guilty. $t the trial, he invoked self-defense. !inding thatpetitioner%s narration was &well-nigh inconceivable& due to his vacillating statements at different stages ofthetrial, 'he(egional 'rial Court of )anilaruledfindin,theaccused,uiltyof thecri-echar,edinthe/nfor-ation beyond reasonable doubt.I''()*1. Whether prosecution witness *ermudes% testimony was worthy of credence despite his earliersworn statement corroborating the petitioner%s testimony+%. Whether or not the appellant acted in self-defenseH)+d*,etitioner seeks ac-uittal based on the supposed unlawful aggression directed against him by thedeceased 'he defense intended to prove self-defense with the following evidence" ./0 *ermudes% swornstatement that petitioner waswalkingawaywhenhewasattackedbythedeceased .10 petitioner%stestimonytothesameeffect and.20 thenotoriouscharacter of thedeceasedwhichbuttressestheallegation of unlawful aggression against petitioner.P"o+o,()* Con')-()n#) o. In/o01n, S)+.23).)n')!irmly entrenched is the rule that where the accused invokes self-defense, it becomes incumbentupon him to prove by clear and convincing evidence that he indeed acted in defense of himself. 'heburden of proving that the killing was 3ustified and that he incurred no criminal liability therefor shifts uponhim. He must rely on the strength of his own evidence and not on the weakness of that of the prosecutionfor,even if theprosecution evidenceisweak, it cannot be disbelieved aftertheaccusedhimselfhasadmitted the killing. C")d141+15y o. 615n)'')'Weagree. &$naffidavit beingtakene4parteisalmost alwaysincompleteandofteninaccurate,sometimes from partial suggestion, and sometimes from want of suggestion and in-uiries, without the aidof which the witness may be unable to recallthe connected collateralcircumstances necessary for thecorrection of the first suggestion of his memory and for his accurate recollection of all that belongs to thesub3ect.&5/67 $naffidavit will not alwaysdiscloseall thefactsandwill, oftentimesandwithout design,describe some occurrences without the deponent detecting inaccuracies or contradictions.5/87 $s a matter of fact, the Salaysay and *ermudes% testimony in court are not grossly inconsistent witheach other. 'his is substantially the same as his direct testimony that the deceased asked petitioner-why he waswalking away instead of finishing the fight. 'hey resumed stabbing each other as a result. Clearly, in boththe Salaysay and *ermudes% testimony, the deceased and the petitioner agreed to fight. 'his was whatthe trial court had found and what (espondent Court affirmed. 9t must also be mentioned that the defensecounsel allowed the case to be submitted for decision without cross-e4amining *ermudes, failing therebytotakeadvantageof anopportunitytoimpeach.assumingthat hecould0 *ermudes% credibilityandtestimony.No Un+a7.(+ A,,")''1on 6$)") P"o5a,on1'5' A,"))d 5o F1,$59tisa hornbook doctrine thatwhen self-defenseisinvoked,the burdenofevidenceshifts totheappellant to prove the elements of that claim, i.e., ./0 unlawful aggression on the part of the victim, .10reasonable necessity of the means employed to prevent or repel it, and .20 lack of sufficient provocationon the part of the person defending himself. *ut absent the essentialelement of unlawfulaggression,there is no self-defense. 9nthecaseat bar, theCourt findsthat theevidenceonrecorddoesnot support petitioner%scontention that the unlawful aggressor was the deceased.!irstly, the trial court did not give credence to petitioner%s testimony because &.a0side from the factthat there is much to be desired from the deportment of the accused when he .sic0 testified, his testimonyis not credible. Weagree. 'hegist of petitioner%stestimonyisthat hedoesnot remember havingstabbedthedeceased. 9t is inconsistent with self-defense which in essence is an admission of the killing in order topreserve one%s life or limb. *eing evasive, such testimony does not help at all in establishing self-defense.!urther, petitioner%s self-defense is not corroborated by separate competent evidence. ,itted against*ermudes% testimony, it pales in comparison and loses probative value. 'he plea of self-defense cannotbe 3ustifiably entertained where it is not only uncorroborated by any separate competent evidence but alsoe4tremely doubtful in itself. Secondly, as pointed out by (espondent Court, the aspersion cast by the defense on the deceasedasthebadgeof notorietyintheneighborhood&e4posedtheweaknessof itscause. 'rue, themoralcharacter of the offended party may be proven in evidence to establish &in any reasonable degree& theprobability of the offense charged, and his -uarrelsome nature may indicate that he started the unlawfulaggression. However, such evidence presented merely to establish a probability cannot prevail over factssufficiently proven during trial. 'hirdly and more importantly, where the parties mutually agree to fight, itbecomes immaterial who attacks or receives the wound first, for the first act of force is incidental to thefight itself and in no wise is it an unwarranted and une4pected aggression which alone can legali:e self-defense. 9n this situation, the circumstances modifying criminal liability cannot be applied to either party.Conse-uently, the 3uristic idea of self-defense is precluded. !inally, the -uestion of whether appellant acted in self-defense is essentially a -uestion of fact.'hisbeing so and in the absence of a showing that (espondent Court and the trial court failed to appreciatefacts or circumstances of such weight and substance that would have merited the appellant%s ac-uittal,this Court finds no compelling reason to disturb the ruling of (espondent Court that appellant did not actin self defense.6HEREFORE, the assailed ;ecision and (esolution of (espondent Court are hereby $!!9()