This  case is before us on appeal from the Court of First Instance of Cagayan,  which found appellant guilty of double murder and  frustrated murder  and  sentenced her  to reclusion perpetua, with its accessory  penalties;  to indemnify the heirs of each  of  the  deceased  Honorata Badajos and Erlinda Baturi in the amount of P6,000.00; and  to pay the costs.  In the brief for  appellee,  the Solicitor   General recommends  a verdict of acquittal.

Mrs. Aniceta Caronan was the owner and manager of a sari-sari  store and panciteria in the public  market of Tuguegarao, Cagayan, and  of a small rice mill across the street, a  few meters from and  on the same side as the house where she and her family were residing.  In the market was  another sari-sari store operated  by  Mrs. Caronan's niece,  Honorata Badajos, capitalized  with money lent to her by her aunt Mrs. Caronan had several helpers: appellant, whose work was to launder for  the family and look after the children; Cristina de la Cruz,  the  family cook; Valeriana Baturi, a salesgirl and Honorata's sister-in-law; Mariano Baturi, Honorata's husband, the rice mill machinists; and Gregorio Baquiran, a helper at the mill.

The Baturis Mariano, Honorata  and  their   small daughter Erlinda had their  own house, but were allowed to use the kitchen in the residence of the Caronans. The testimony of Rosa Bacud, a niece of Honorata  and a witness for  the  prosecution,  is that  on  October  23,  1956, at about 11:00 o'clock in the  morning, she was in that kitchen cooking rice and pinakbet, an  Ilocano  dish made up  of an  assortment  of vegetables  seasoned  with "bagoong."  With her at   the time were Cristina de la Cruz and appellant. Rosa left the kitchen to get a can of "bagoong" from her employer's store across the street.   Upon her  return, she said,  she saw  appellant lift the cover  of the pot in which the pinakbet  was being cooked and put something inside. Appellant then replaced the cover and, together with   Cristina, left  the kitchen for one  of the rooms of the house. When  Rosa opened  the  pet  to put in the "bagoong," she noticed some whitish substance, which she presumed to be salt, spread over  the contents.  As soon as the rice and  the pinakbet were  ready she took them to the store where she,  Honorata and the latter's daughter Erlinda had their lunch.  Immediately after the meal all three started vomiting violently.  A  little later Valeriana came and took them to the clinic of Dr. Remedios Reyes.

Erlinda Baturi died at about 5:00 o'clock that afternoon, followed by Honorata at about  9:00.  Rosa  Bacud survived. Post mortem examination revealed that Honorata was two  months in the family way and that she and her daughter had died of arsenic poisoning, a finding confirmed  by the chemical analysis later made of portions of their intestines.

Valeriana Baturi was also presented as a witness for the prosecution.  Her job was that of  salesgirl at the store  of the Caronans.   At eleven in the morning of the day of the incident, she said, she got her feet muddy and so went to wash them in the bathroom adjoining the kitchen of the Caronan residence. It was then that she saw appellant  put something inside  the  pot containing the vegetable  concoction. On this  point, however,  her  testimony is  far  from  clear. In one instance she  said that "coming out from the tienda,"  she had "to go directly to the bathroom through the kitchen."   She had  just washed her feet and was entering the kitchen from the   bathroom when she saw appellant as above  related.  In the very next breath she said she was already in the dining room, where she met Rosa Bacud carrying a can of "bagoong," when she turned her face and saw appellant putting something inside  the  pot of pinakbet.   And still later, she averred that she met Rosa Bacud in the sala of  the house and that it was from there that, upon looking  back, she saw appellant perform  the act described.

The case for the prosecution depends upon the weight that must be  given to  the   testimony of these  two witnesses Rosa Bacud and Valeriana  Baturi and whether, assuming  that they spoke the truth,  the evidence proves appellant's guilt beyond reasonable  doubt.
Rosa  Bacud's testimony is suspect.  She  thought the whitish substance appellant had placed with  the pinakbet was salt.  Yet she put in the "bagoong" anyway, without first testing the vegetables to  find out  if they were already salty enough.   She did not even ask appellant what it was that she added,  and  why;  or tell her  employer, Mrs. Caronan, what appellant had done.  Rosa Bacud was first investigated  by Colonel Peñaflor of the Constabulary on  the third  day after the  incident.  The  investigation was put down in writing.  She did not say a word, however,  about appellant's action.  It was  only  in her subsequent  affidavit, taken  by  Sergeant  Jerez,  that  she mentioned  the  matter for the first time.

Valeriana Baturi's apparently incriminating story fares no  better under  closer scrutiny.  As  already noted, she said she saw only once appellant's act of lifting the lid of the pot, but  in her testimony mentioned three different places from which she saw it.  And Aniceta  Caronan, her own employer  and aunt  of the  deceased  Honorata Badajos, categorically contradicted Valeriana on several matters, including the incident of Valeriana's getting mud in her feet.  But what is of material  importance  is Aniceta's emphatic affirmation  of  the  facts  (1) that in her presence her husband, Arturo  Caronan,   asked Valeriana what had happened when they all saw the poison victims vomiting and Valeriana  answered she did not know as she was in the tienda all the  time;  (2) that appellant, questioned  on  the same occasion,  gave  the same reply, saying that she never left the place where  she was washing clothes the whole morning;  (3)  that Valeriana did not give the lie to appellant then, which she should have done if she had indeed seen the latter tamper with the pinakbet that  was cooking; and (4)  that there was no bathroom   in the house adjoining and accessible  from the kitchen.  The only bathroom, according to Mrs. Caronan, was in  the camarin where the rice-mill was located,  and the only way to go there  from the tienda was across the street without  passing through the kitchen of the house, because there was a tall bamboo fence separating the house from the camarin. Conversely, Mrs. Caronan said, to go to the kitchen  from the bathroom  one had to go out to the street and  then turn back  to the house on the other side of the fence.  This last fact about the bathroom was confirmed  by Arturo Caronan.  He further testified that after  the incident Colonel Peñaflor called  him  and his three maids for investigations, and Valeriana Baturi denied knowing anything because she was tending the store all  the time.   It was  the  same  answer  she gave  him when he questioned  her  before  the  poison  victims  were taken to the clinic of Dr. Reyes, as well to the two physicians  themselves in the clinic upon  arrival there.

Appellant  denied the charge against her.  She testified that she never left the bathroom near the rice-mill where she was washing clothes  until she  was called by her employer after the poisoning.  The  evidence shows no motive on her  part to do away with the victims.   To  be  sure, Rosa Bacud made this statement: "My aunt Honorata Badajos suspected that  Aurelia Mabborang is the paramour of Mariano  Baturi  (Honorata's husband)."  This,  however, besides being hearsay and opinion evidence, was belied  not only by appellant but also by the fact that Mariano Baturi married another woman shortly after he was widowed, while appellant married Gregorio Baquiran, the helper at the rice mill.

The conviction of appellant rests entirely on circumstantial  evidence.  The weakest link in  the chain  is at the same time the most  vital, namely, the circumstance that the pinakbet was the agency which carried the  poison. There is no satisfactory proof of this.   What was left of the pinakbet (there must have been,  if only a small portion) was not  subjected  to chemical analysis.   It could have been the culprit, of  course,  but  the mere probability that it  was  does not satisfy the test of moral certainty which applies in criminal cases.  The  arsenic could conceivably have   been  mixed  with the rice,  or  with the "ampalaya"  and other vegetables  before they were gathered,  administered  in the form of insecticide  and deposited in their skin folds and ridges. This last probability was conceded  by the NBI  chemist  who testified as an expert in this  case.

In the face of the evidence, we are convinced that the recommendation  for acquittal  made  by the Solicitor General is justified.

The judgment appealed from is therefore reversed and appellant is acquitted, with costs de oficio.

Bengzon, C. J., Padilla, Bautista Angelo, Labrador, Concepcion,  Barrera, Paredes, Dizon and  Regala, JJ., concur.