Short answer. When a person attacks, employs force against, seriously intimidates or seriously resists a person in authority or an agent of authority who is performing official duties, or on the occasion of that performance, and there is no public uprising. Laying hands on a person in authority, using a weapon, or being a public officer raises the penalty.
What the law says
shall attack, employ force, or seriously intimidate or resist any person in authority of any of his agents, while engaged in the performance of official duties, or on occasion of such performance
Revised Penal Code, Article 148 — Direct Assault On Authority. Read the full provision →
Who counts, and when
A police officer is ordinarily an agent of a person in authority; persons in authority are those vested with jurisdiction on their own, such as a mayor, a judge, a barangay chairman, or a teacher in certain situations. The distinction matters because the heavier penalty attaches when the offender lays hands upon a person in authority. Equally important is timing. The officer must be engaged in the performance of official duties, or the incident must occur on the occasion of that performance — so a grudge attack later, because of an earlier arrest, can still fall inside, while a purely private quarrel with an off-duty officer generally does not.
Not every resistance is direct assault
This is the point that decides most cases. The article requires an attack, force, or serious intimidation or resistance. Pulling your arm away, arguing loudly, refusing to answer questions, or going limp is usually not enough; the Revised Penal Code deals with lesser conduct under the separate offence of resistance and disobedience to an agent of a person in authority, which carries a much lighter penalty. Prosecutors and defence counsel fight over exactly this line, and it is decided by what the accused physically did, not by how offended the officer was. The article also requires that the act be done without a public uprising, which separates it from rebellion and sedition.
The two penalty tiers, and the fines today
The heavier tier is prisión correccional in its medium and maximum periods with a fine not exceeding two hundred thousand pesos, and it applies in three situations: the assault is committed with a weapon, the offender is himself a public officer or employee, or the offender lays hands upon a person in authority. If none of those circumstances is present, the penalty is prisión correccional in its minimum period with a fine not exceeding one hundred thousand pesos. Both peso figures are current because of Republic Act No. 10951, enacted in 2017, which revised the fines throughout the Code. Any source quoting the old 1930 amounts is out of date.
If you have been charged
Direct assault is frequently filed together with physical injuries or in answer to a complaint the citizen made first, so the file often contains two competing narratives written the same night. Do not give a narrative statement at the station without counsel; explanations meant to minimise the incident routinely end up supplying the missing element. Preserve everything that fixes what actually happened — body-camera or CCTV footage, medical certificates, the blotter entry, the names of bystanders — and ask for it early, because footage is retained for a short time. No lawyer can promise a dismissal, but the difference an early, documented defence makes at the prosecutor's level is substantial.