OPINION OF THE COURT BY
HAYASHI, J.Defendant-Appellant Timothy E. Knoeppel (Defendant) appeals from the order and judgment entered in the Family Court of the First Circuit on May 10, 1989. The order denied Defendant’s motion to dismiss, and the judgment was entered in accor*169dance with the family court’s finding of Defendant guilty as charged for the offense of abuse of a family or household member (HRS § 709-906). We reverse.
I.
FACTUAL BACKGROUND
On February 26, 1989, Defendant shared an apartment in Honolulu with Steven and Deana. Following a dispute between Defendant and Deana in the living room, Defendant slapped Deana across the right side of her face with the back of his hand. Defendant was subsequently arrested.
The day following the incident and arrest, February 27,1989, a complaint signed by Police Officer Samson Nava (Officer Nava), the arresting officer, was filed with the family court. The complaint charged Defendant with committing the offense of abuse of a family or household member, a misdemeanor. This one-page, standard form complaint did not contain: 1) a signature line for the prosecutor; nor 2) the signature of any prosecutor.
At his arraignment on March 13, 1989, Defendant, who was then represented by a deputy public defender, entered a plea of not guilty.
On April 13, 1989, Defendant moved to dismiss, asserting that: 1) the case was initiated by the filing of an illegal complaint; and thus 2) the family court lacked the requisite jurisdiction to adjudicate the case. Following a hearing, the family court orally denied Defendant’s motion to dismiss.
Trial then commenced, and Defendant was found guilty of the charged offense.
Following the entry of the order and judgment, Defendant timely appealed.
*170II.
HRPP RULE 7
Rule 81(c) of the Hawaii Family Court Rules states that “[c]ases for adults charged with [the] commission of a crime coming within the jurisdiction of the family courts shall be governed by the Hawaii Rules of Penal Procedure.” Hawaii Rules of Penal Procedure (HRPP) Rule 7, in turn, reads in relevant part (emphasis added):
THE INDICTMENT, COMPLAINT AND ORAL CHARGE.
(a) Use of Indictment, Complaint or Oral Charge. The charge against a defendant is an indictment, a complaint or an oral charge filed in court. A felony shall be prosecuted by an indictment or a complaint. Any other offense may be prosecuted by an indictment, a complaint, or an oral charge.
(d) Nature and Contents. The charge shall be a plain, concise and definite written statement of the essential facts constituting the offense charged; provided that an oral charge need not be in writing.... A complaint shall be signed by the prosecutor, or it shall be sworn to or affirmed in writing before the prosecutor by the complaining witness and be signed by the prosecutor[]____ Formal defects, including error in the citation or its omission, shall not be ground for dismissal of the charge or for reversal of a conviction if the defect did not mislead the defendant to his prejudice.
Defendant contends the family court erred in denying his motion to dismiss. According to Defendant’s theory: 1) since the complaint was only signed by Officer Nava and wás not also signed by the prosecutor, the complaint was fatally defective; and *171therefore 2) the resulting judgment is invalid since the case was never properly initiated.
Essentially, Defendant urges a mandatory reading of the signature provisions of HRPP Rule 7(d). We agree.
The plain and unambiguous language of HRPP Rule 7(d) mandates that a criminal complaint shall be: 1) signed by the prosecutor; or 2) sworn to or affirmed in writing before the prosecutor by the complaining witness and be signed by the prosecutor. Cf. State v. Rodgers, 70 Haw. 156, 766 P.2d 675 (1988) (HRPP Rule 12(e) mandates that a motion to suppress shall be determined before trial, and where factual issues are involved in determining the motion, the trial court shall state its essential findings on the record).
The absence of the prosecutor’s signature on the complaint, therefore, rendered the complaint fatally defective. The resulting judgment, in turn, is null and of no effect.
We reject Plaintiff-Appellee State of Hawaii’s (State) contention that the omission of the prosecutor’s signature on the complaint constitutes a formal defect, and thus, is not a proper ground for dismissal where no prejudice results to the defendant. Since the prosecutor is generally charged with the responsibility of determining whether or not to instigate a formal criminal proceeding, see Amemiya v. Sapienza, 63 Haw. 424, 629 P.2d 1126 (1981) (the public prosecutor has been delegated with the primary authority and responsibility for initiating and conducting criminal prosecutions within his county jurisdiction), the absence of the prosecutor’s signature on the complaint, in our view, is not a mere formal defect. See also HRS § 709-906(7) (the family or household member who has been physically abused or harmed by another person may file a criminal complaint through the prosecuting attorney of the applicable county).
We also reject State’s argument that “[t]he prosecutor . . . elected to charge the [Defendant verbally at the arraignment[,]” *172and “[b]y electing to charge by reading, the prosecutor cured the ... defect in the complaint.” Answering Brief at 7-8.
Chris P. Bertelmann (Bertelmann & Pascual, of counsel), for Defendant-Appellant. Glenn T. Taniguchi, Deputy Prosecuting Attorney, for Plaintiff-Appellee.The record indicates that Defendant: 1) was not orally charged by the prosecutor at the arraignment; and 2) did not waive any formal reading of the charge.
III.
CONCLUSION
Based on the foregoing reasons, we reverse the order and judgment. Reversed.