1) Preliminary Investigation in context

A preliminary investigation (PI) is an inquiry conducted by a public prosecutor (or other authorized investigating officer) to determine whether there is probable cause to believe that (a) a crime has been committed and (b) the respondent is probably guilty and should be held for trial. It is not a trial on the merits; it is a screening mechanism before the filing of an Information in court.

In the Philippines, PI practice is governed chiefly by:

The Revised Rules of Criminal Procedure, particularly Rule 112 (as amended), and
Department of Justice/National Prosecution Service (DOJ/NPS) issuances that provide detailed prosecutorial procedures (often covering submissions like reply and rejoinder affidavits, case calendaring, and internal routing).

PI is generally required for offenses where the penalty prescribed is at least 4 years, 2 months, and 1 day (the threshold used in Rule 112), unless a special law or rule provides otherwise.

2) What a counter-affidavit is (and why it matters)

A counter-affidavit is the respondent’s primary written submission in PI. It is both:

A defensive narrative (the respondent’s sworn version of events and defenses), and
Evidence (since PI is largely paper-based, built on sworn statements and attached documents).

A counter-affidavit should be treated as the respondent’s best chance to:

Knock out probable cause early,
Establish defenses (e.g., denial, alibi with corroboration, lack of intent, justification, authority, mistake of fact),
Highlight fatal legal defects (e.g., prescription, lack of jurisdiction, failure to allege essential elements),
Present exculpatory documents and witnesses, and
Explain circumstances that may not appear from the complainant’s side.

Because PI is not a full-blown trial, prosecutors decide probable cause primarily from what is submitted. A weak or late counter-affidavit can result in the case being resolved largely on the complaint alone.

3) How the PI reaches the counter-affidavit stage

(A) Filing of the complaint

The complainant files a complaint-affidavit (and supporting affidavits/documents) with the prosecutor’s office that has territorial jurisdiction (generally, where the offense or any of its essential elements occurred).

(B) Issuance of subpoena

If the investigating prosecutor finds the complaint sufficient in form and substance to require an answer, a subpoena is issued to the respondent. The subpoena typically:

Directs the respondent to submit a counter-affidavit and supporting evidence within the period fixed by the rules, and
Includes copies of the complaint and its supporting evidence (or makes them available for receipt).

(C) Service of subpoena on respondent

Service is ordinarily made through the prosecutor’s office using practical modes (commonly personal service or mail/courier to the respondent’s address). The key due process idea is that the respondent must be given notice and a meaningful opportunity to submit a counter-affidavit.

If the respondent is represented by counsel, many offices will recognize service through counsel once an appearance is entered, but practices vary; safest is to ensure the prosecutor has the correct addresses for both respondent and counsel.

4) Deadline to file the counter-affidavit

General rule: 10 days

Under Rule 112, once the respondent receives the subpoena (with the complaint and supporting evidence), the respondent is typically given ten (10) days to submit:

Counter-affidavit, and
Affidavits of witnesses and other supporting documents relied upon.

Extensions

A request for extension may be allowed for good cause, subject to the investigating prosecutor’s discretion and office practice. It is commonly requested in situations like:

Voluminous records,
Need to secure documents from third parties,
Need for translation, authentication, or consular notarization,
Multiple respondents requiring coordination.

Because PI is intended to be summary, prosecutors often frown on long delays; requests should be specific (how many days, why necessary, what steps are being taken).

Failure to file within the period: waiver and ex parte resolution

If the respondent does not file a counter-affidavit within the allowed period (including any granted extension), the respondent is typically deemed to have waived the right to submit. The prosecutor may then resolve the case based on the complaint and evidence on record.

This does not automatically mean the respondent “loses,” but it frequently increases the risk of a finding of probable cause.

5) Form and content requirements of a counter-affidavit

(A) Must be sworn

A counter-affidavit is an affidavit, so it must be sworn before an authorized officer (e.g., prosecutor administering oath, notary public, or Philippine consular officer if executed abroad). Unsigned/unsworn statements are generally not treated as affidavits.

(B) Should address the accusations specifically

A strong counter-affidavit:

Responds to the complainant’s factual allegations point-by-point,
Identifies missing elements of the offense,
Explains inconsistencies,
Provides an alternative narrative supported by documents and witness affidavits.

(C) Include all defenses and supporting evidence you intend to rely on

PI is affidavit-driven. Respondents should attach:

Documentary evidence (contracts, screenshots, medical records, certifications, official records),
Affidavits of witnesses,
Authorizations/board resolutions (for corporate matters),
Technical reports (if relevant),
Proof of authority/ownership/consent (common in property and cyber-related complaints).

In practice, prosecutors often treat PI as a “submit what you have now” process. Withholding key defenses or evidence can be risky, because the resolution may be issued without further hearings.

(D) Authentication and clarity of annexes

Common best practices:

Mark documents as annexes (Annex “A,” “B,” etc.),
Provide brief descriptions,
Ensure legibility,
Use certified true copies where needed (especially for official records),
Explain the relevance of each annex in the affidavit text.

(E) Technical rules are relaxed—but organization matters

PI is not governed by strict rules of evidence in the same way as trial, but prosecutors still assess credibility, relevance, consistency, and sufficiency. A disorganized submission can undermine otherwise strong defenses.

6) Filing mechanics: where, how, and in what quantity

(A) Where to file

The counter-affidavit is filed with the Office of the Prosecutor handling the PI (city/provincial prosecutor, or other authorized investigating office like the Ombudsman in cases within its jurisdiction).

(B) Number of copies

Requirements vary by office, but commonly the prosecutor requires enough copies for:

The official case record,
The complainant (and sometimes co-complainants),
Co-respondents (in some offices), and
The respondent’s receiving copy.

Because copy requirements are office-specific, parties typically comply with the subpoena instructions or the receiving desk’s guidance. When unsure, filing with extra copies avoids delays.

(C) Proof of filing

Always secure:

A receiving stamp on your copy, or
Official receipt/acknowledgment from the receiving unit, or
Official email acknowledgment (if the office allows e-filing).

7) Service rules: who must receive the counter-affidavit, and how

(A) Core service principle: the other party must be furnished

Due process in PI is adversarial in the sense that each party should have the opportunity to respond to the other’s submissions. Thus, the complainant should receive a copy of the counter-affidavit (and attachments) so that a reply may be filed.

(B) Who effects service?

In many PI setups:

The respondent files the counter-affidavit with the prosecutor, and
The prosecutor’s office ensures that the complainant is furnished a copy (or requires the respondent to furnish and submit proof of service).

Office practices differ:

Some require party-service (respondent serves complainant directly and submits proof of service).
Others treat furnishing as part of prosecutorial control (release or pickup arrangements through the prosecutor’s office).

To avoid disputes, the safest approach is to furnish the complainant and provide proof of service (unless the office expressly instructs otherwise).

(C) Modes of service commonly recognized

Practical modes typically include:

Personal service to the party or counsel (with signed receipt),
Registered mail (with registry receipt and tracking details),
Courier (with delivery confirmation),
Electronic service (email) where the prosecutor’s office expressly allows or directs it (especially under local administrative arrangements).

Because PI is administrative/executive in character, prosecutors often accept reasonable proof that the adverse party was furnished, even if the method is not perfectly aligned with court-style service rules—so long as fairness is maintained.

(D) Proof of service

Common proof includes:

Acknowledgment/receiving copy signed by the recipient,
Registry receipt and later the return card (if available),
Courier waybill and delivery confirmation,
Email sent items plus acknowledgment (if recognized).

Attach proof of service to a short manifestation or include it as an annex with your filing.

(E) What must be served?

At minimum:

The counter-affidavit, and
The supporting documents and witness affidavits relied upon.

Service of incomplete annexes can trigger motions to expunge, requests for re-furnishing, or claims of denial of due process.

8) Reply and rejoinder: the service chain that follows

Although Rule 112 emphasizes the respondent’s counter-affidavit, DOJ/NPS practice commonly provides a structured exchange:

Counter-affidavit (respondent)
Reply-affidavit (complainant) — responding to defenses and new matters raised
Rejoinder-affidavit (respondent) — limited response to new matters in the reply

Each step usually comes with short deadlines set by office practice or by the investigating prosecutor, and each submission should be furnished to the other side.

A frequent prosecutorial approach is to disallow endless back-and-forth; once the parties have had a fair chance to present their sides, the case is submitted for resolution.

9) Clarificatory hearing and its relation to affidavits

(A) Discretionary nature

A clarificatory hearing may be conducted if the investigating prosecutor believes it is necessary to clarify ambiguous points. It is not automatic.

(B) No full trial rights

In PI, parties generally do not enjoy the full trial-level right to cross-examine in the same manner. The prosecutor may ask questions; parties may be allowed to submit clarificatory questions through the prosecutor, depending on the office.

(C) Failure to appear

Non-appearance can have adverse consequences, but the primary risk remains the documentary record: the prosecutor may resolve based on submitted affidavits and evidence.

10) Special situations affecting filing/service of counter-affidavits

(A) Multiple respondents

Each respondent typically receives a subpoena and may file a separate counter-affidavit. When defenses overlap, submissions should still be individualized enough to address each respondent’s alleged participation.

Service/furnishing becomes heavier: the complainant must receive the counter-affidavits (and annexes) of each respondent, as required by the investigating office.

(B) Corporate respondents or officers

If the respondent is a corporation or a corporate officer:

Ensure the affidavit identifies capacity/authority,
Attach authority documents (e.g., secretary’s certificate, board resolution) when relevant,
Service addresses often use the corporation’s registered/principal office, and service on counsel becomes important once counsel appears.

(C) Respondent abroad

A counter-affidavit executed abroad is commonly sworn before:

A Philippine consular officer, or
A foreign notary, with authentication/apostille considerations depending on the office’s requirements and the nature of the documents.

Mailing/service delays should be anticipated; extension requests should be supported with specifics.

(D) Cases under the Ombudsman or special investigative bodies

If the case falls under the Office of the Ombudsman (e.g., certain cases involving public officers and graft-related offenses), the governing procedural rules differ in details, but the basic logic remains: sworn counter-affidavits, deadlines, furnishing/service, and opportunity to reply.

(E) Inquest vs regular PI

When an arrest occurs without a warrant and an inquest is conducted, a respondent may, in many situations, request a regular preliminary investigation. The mechanics (including time-sensitive custody and bail considerations) can change the practical timeline for filing counter-affidavits, but the core requirement—submitting a sworn counter-affidavit with supporting evidence and furnishing the adverse party—remains central once the matter proceeds as a regular PI.

11) Common procedural issues and guiding principles

(A) PI is statutory; due process is essential once it is undertaken

While PI is not the same as the constitutional right to trial, once the rules provide PI, the process must still satisfy fairness: notice and an opportunity to explain one’s side.

(B) “No motions” mindset

Rule 112 contemplates a streamlined process and generally discourages dilatory pleadings. Many prosecutors will not entertain motions that mimic trial practice (motions to dismiss, motions for bill of particulars), preferring that issues be raised in the counter-affidavit itself. Some legal issues may still be raised as part of the counter-affidavit’s arguments (e.g., lack of elements, jurisdictional defects, prescription).

(C) New matters must be met fairly

If the complainant raises new facts in a reply-affidavit, fairness usually requires giving the respondent a chance to address those new matters (often through a rejoinder or a directed submission).

(D) The record you build controls

Prosecutors typically resolve based on:

Internal consistency of sworn statements,
Corroboration by documents,
Plausibility and detail,
Objective indicators (timestamps, official records, third-party affidavits),
Indicators of fabrication or afterthought defenses.

12) Practical checklist for a compliant counter-affidavit package

Counter-affidavit proper

Caption/title matching the PI docket
Sworn narrative with numbered paragraphs
Direct responses to key allegations
Legal arguments tied to elements of the offense
Clear “prayer” (dismissal for lack of probable cause)

Attachments

Witness affidavits (sworn)
Documentary annexes (legible, marked, explained)
Authority documents (when acting for a corporation/organization)
Proofs that negate elements (e.g., consent, authority, absence, lack of demand, lack of damage)

Filing

Correct prosecutor’s office/unit
Correct number of copies
Receiving proof (stamp/acknowledgment)

Service/Furnishing

Copy furnished to complainant (and counsel, if any)
Proof of service (receipt, registry/courier proof, authorized email proof if applicable)
Complete annexes included in the furnished set

13) Summary of the core rules

Subpoena + complaint/evidence triggers the respondent’s obligation to answer.
Respondent files a sworn counter-affidavit (with witness affidavits and documents) typically within 10 days from receipt, unless an extension is granted.
Failure to file on time is commonly treated as a waiver, and the PI may be resolved ex parte based on the complainant’s submissions.
The complainant must be furnished a copy of the counter-affidavit and annexes to preserve fairness and allow a reply.
Prosecutors may allow reply and rejoinder affidavits and may conduct a clarificatory hearing if needed, but the process remains primarily affidavit-based.
Proof of filing and proof of furnishing/service are critical to avoid claims of denial of due process or incomplete service.