My brother is involved in a grave threats case where the complainant accused him of threatening to kill him, the decision regarding this case is scheduled this coming March. We feel that he may lose the case hence we want to prepare for whatever will happen. What are the standing penalties on such a case, will he go to jail? For how long? Thank you for any information that you can share with us.

yes, the penalty would be arresto mayor which duration of penalty shall be from one month and one day to six months.

The penalties for grave threats are different depending on the acts committed.

He shall be punished with the penalty next lower in degree than that prescribed by law for the crime he threatened to commit if he demanded money or any condition and he attained his purpose. So, if in case he threatened to commit Homicide, the penalty next lower in Degree than the penalty (Reclusion Temporal) will be imposed which is Prision Mayor (6 years and 1 day to 12 years).

If he did not attain his purpose, he will be punished by the penalty 2 degrees lower as mentioned by thata.