1) The basic idea: criminal cases are prosecuted by the State

In the Philippines, a criminal action is prosecuted in the name of the People of the Philippines. The public prosecutor (city/provincial prosecutor or their authorized assistant) has the duty to prosecute criminal actions and, in general, controls the conduct of the prosecution in court.

A private prosecutor is a private lawyer who participates in the prosecution because the private offended party (the victim) has a direct interest—primarily to pursue the civil liability arising from the crime—but only under the direction and control of the public prosecutor.

This framework matters a lot for illegal possession of firearms and illegal possession of dangerous drugs, because these are typically “public crimes” where the offended party is the State, not a private individual.

2) What “private prosecutor” means in practice

A. Who is the private prosecutor really representing?

A private prosecutor represents the private offended party (the person directly injured by the criminal act) for purposes of:

civil liability ex delicto (damages and restitution arising from the crime), and
assisting the public prosecutor in proving the criminal case, so long as the public prosecutor allows it.

B. Always subordinate to the public prosecutor

Even when allowed to participate, a private prosecutor:

cannot “take over” the case from the public prosecutor,
cannot file an Information in their own name,
cannot decide what charge will be filed,
cannot withdraw the case,
cannot control plea bargaining or dismissals (these remain prosecutorial functions, subject to court approval where required), and
cannot compromise criminal liability (criminal liability generally cannot be compromised; only the civil aspect may be compromised, and even that has limits).

The public prosecutor remains the captain of the ship in court.

3) Why private prosecutors are uncommon in “possession” cases

A. In most possession cases, there is no private offended party

Illegal possession of dangerous drugs (commonly prosecuted under R.A. No. 9165, as amended) and illegal possession of firearms (commonly prosecuted under R.A. No. 10591 and related laws) are usually treated as offenses against public order and public safety.

That means:

the State is the offended party, and
there is usually no individual victim who can appear as a private offended party for civil damages arising directly from the mere act of possession.

So, in a typical buy-bust drug possession case or a checkpoint firearm possession case, there is usually no proper legal “client” for a private prosecutor in the technical sense.

B. “Complainant” is not always the “private offended party”

Police officers, poseur-buyers, arresting officers, and government agencies are often the complainants/witnesses, but they are not, by that fact alone, the private offended party contemplated for a private prosecutor’s appearance.

4) When a private prosecutor can properly appear in these cases

A private prosecutor can have a legitimate role when the possession case is tied to a crime with a real private victim, or when the case configuration creates a civil aspect with a private claimant.

Common situations include:

A. Possession plus a crime with a private victim

Examples:

Illegal possession of firearm with homicide or murder arising from the same incident (depending on how charged under current statutes and jurisprudence at the time),
Drugs possession cases with physical injuries, threats, robbery, or other offenses where a specific person suffered damage,
Possession discovered in the course of an incident where a person’s property was damaged or taken.

In those scenarios, the private offended party (e.g., the heirs of a homicide victim, or a person injured) may seek civil damages, and a private prosecutor may appear for that private offended party—even if the prosecution also includes possession-related charges.

B. A separate civil interest clearly linked to the criminal action

While the default rule is that civil liability is impliedly instituted with the criminal action (unless waived, reserved, or separately filed), in pure possession cases there is often no direct civil liability to a private party. But where the facts create compensable harm to an identifiable person, the civil aspect becomes meaningful, and a private prosecutor’s appearance becomes more defensible.

C. Representation of a victim-witness (not as “private prosecutor,” but as counsel)

Sometimes a private lawyer assists a witness or complainant (including law enforcement personnel) as private counsel for matters like:

protecting the witness’s rights,
dealing with administrative exposure,
coordinating testimony preparation.

That lawyer is not necessarily a “private prosecutor” in the technical Rules-of-Court sense—unless there is a true private offended party with a civil claim.

5) “Special counsel” or deputized private lawyers: a different pathway

Separate from the concept of a private prosecutor for a private offended party, the government may authorize or deputize lawyers to assist in prosecution (depending on the legal basis and the office involved). This is closer to special counsel/special prosecutor arrangements.

Key distinctions:

A deputized/special counsel assists the State’s prosecution function by authority of the proper office.
A private prosecutor assists because of a private offended party’s civil interest.
In both, court appearances are still subject to rules and the public prosecutor’s control in the courtroom.

If someone is attempting to appear in a pure possession case without a private offended party, the more legally coherent route (if allowed) is usually some form of authorized assistance to the public prosecutor—not “private prosecution” based on a private victim.

6) What a private prosecutor may do (when properly allowed)

When the private prosecutor is properly in the case (i.e., there is a private offended party and civil liability is being pursued), typical permissible functions include:

A. In court

Assist in witness preparation (coordination and sequencing, not coaching false testimony)
Conduct direct examination/cross-examination with leave of court and under the prosecutor’s control
Make offers of documentary exhibits and help organize evidence presentation
Participate in pre-trial to identify issues, stipulations, and marking of evidence
Argue the civil aspect (damages, restitution, interest) and help prove the extent of injury/loss
File appropriate motions related to the civil liability (e.g., reception of evidence on damages)

B. In the civil aspect (damages)

Prove actual damages (receipts, expenses)
Prove loss of earning capacity (for death/injury cases)
Prove moral damages and exemplary damages when allowed by law and facts
Negotiate settlement only for the civil aspect, subject to legal limits and prosecutorial/court constraints

C. Boundaries

A private prosecutor generally should not:

control case strategy over the objections of the public prosecutor,
file pleadings that effectively usurp prosecutorial discretion,
agree to dismiss or downgrade charges as if they were the prosecutor,
compromise criminal liability, or
use prosecution participation to harass, extort, or gain unfair advantage.

7) What the public prosecutor controls (especially important in drug/firearm cases)

Even when private participation exists, core prosecutorial decisions remain with the public prosecutor, such as:

determination of probable cause and choice of charge (subject to preliminary investigation rules and court oversight where applicable),
whether to present certain witnesses,
whether to enter into stipulations,
plea bargaining positions (subject to prevailing law, DOJ policies, and court approval),
withdrawal of Information or motions to dismiss (subject to court approval).

This is particularly sensitive in R.A. 9165 cases due to strict statutory structures and evolving jurisprudential/administrative policies on handling, custody, and pleas.

8) Stage-by-stage: where a private prosecutor fits (and often doesn’t)

A. Complaint and inquest / preliminary investigation

Drug and firearm possession cases often start with warrantless arrest situations (buy-bust, checkpoint, plain view, hot pursuit) leading to inquest or regular preliminary investigation.
Private prosecutor participation at this stage is usually limited, because the matter is primarily between the respondent and the State, and because pure possession offenses typically have no private offended party.

Where there is a true private victim (e.g., injuries/death), private counsel may help:

prepare affidavits for the victim,
document damages,
respond to counter-affidavits insofar as the civil claim is concerned.

B. Filing in court and trial

This is where private prosecutor participation is most visible—if there is a private offended party and the public prosecutor allows active assistance.

C. Judgment and execution of civil liability

If the accused is convicted and civil damages are awarded, the private prosecutor’s role becomes critical in:

ensuring correct computation and documentation,
enforcing the civil aspect through execution processes (subject to the Rules of Court and court orders).

9) Practical realities in drug and firearm possession prosecutions

Even when there is no private prosecutor, these cases often hinge on recurring litigation issues where a private lawyer (if properly part of the case) can help organize proof:

A. Illegal drugs possession (R.A. 9165): recurring proof issues

legality of arrest and search (warrantless arrest rules, search incident to lawful arrest, consented search, plain view, checkpoints)
integrity of seized items (chain of custody, marking, inventory, photographing, presence/absence of required witnesses, justifications for deviations)
identification of the seized item in court and linkage to laboratory examination
credibility and consistency of law enforcement testimony
handling of evidence from seizure to presentation

B. Illegal firearms possession (R.A. 10591 and related laws): recurring proof issues

proof of lack of license/authority (often shown via official certification)
identity of firearm and ammunition, serial numbers, ballistic examination when relevant
legality of search and seizure (same constitutional issues)
links between possession and any other offense (e.g., use in a crime)

A private prosecutor, when legitimately involved through a private offended party in a related offense, can help the prosecution present a coherent narrative and documentary trail—while staying within ethical boundaries.

10) Ethical and professional responsibility considerations

A private prosecutor’s participation is powerful and risky. Missteps can undermine the case and expose counsel to sanctions.

Common pitfalls:

acting as if the private prosecutor “owns” the prosecution,
using prosecution leverage to force settlements beyond the civil aspect,
appearing without proper authority/standing (no private offended party),
improper public statements that prejudice proceedings,
evidence handling involvement that creates chain-of-custody issues.

Best practice is strict role clarity: assist the prosecution without overstepping prosecutorial functions, and focus on the civil interest of the private offended party where it truly exists.

11) Key takeaways

Most pure illegal possession of drugs/firearms cases have no private offended party, so there is usually no proper “private prosecutor” role in the technical sense.
A private prosecutor becomes relevant when the incident includes a private victim and civil liability (injury, death, property damage, etc.).
Even when properly appearing, the private prosecutor acts under the public prosecutor’s control and cannot perform core prosecutorial acts.
In possession cases, the decisive battlegrounds are typically constitutional search-and-seizure issues and evidence integrity/chain-of-custody; any assisting counsel must avoid creating evidentiary vulnerabilities.

12) Suggested outline for pleading and trial work (when there is a private offended party)

Document all civil damages early (medical bills, funeral expenses, repair costs, proof of income, affidavits of heirs)
Coordinate with the public prosecutor on witness order and exhibit marking
Prepare civil-damages witness testimony separately from the criminal elements
Avoid touching seized items/evidence to prevent chain-of-custody complications
Keep settlement discussions strictly within the civil aspect and properly documented

This article provides general legal information in the Philippine context and is not a substitute for advice on specific facts.