This is an interlocutory appeal by the Commonwealth from a District Court judge’s allowance of the defendant’s motion to suppress. The judge ordered suppression of evidence flowing from the defendant’s extraterritorial
*71
arrest in Framingham by a Natick police officer. The appeal was allowed by a single justice of this court. Mass. R. Crim. P. 15(a),
The judge made the following findings of fact. At 10 p.m. on February 5, 1988, while in a marked Natick police department automobile, Officer William Geissler of the Natick police department observed the defendant’s vehicle traveling at a high rate of speed and passing through a red light. When these observations were made, the defendant and the police officer were in Natick. The officer commenced following the defendant’s vehicle; both vehicles then crossed into the bordering town of Framingham. The defendant pulled his vehicle to the curb within a reasonable period of time from the officer’s command.
The officer approached the vehicle and asked the defendant for his license and registration. The defendant did not have a license with him. Officer Geissler detected a strong odor of alcohol coming from the defendant. The officer asked the defendant to perform two field sobriety tests which, in the officer’s view, the defendant failed. The officer arrested the defendant and took him to the Natick police station where the defendant was subjected to a breathalyzer test, which registered a .15 blood alcohol content. 1
A judge of the District Court ruled that, while the police officer had the authority to stop the defendant in Framingham, he exceeded his authority when he arrested him. The judge granted the defendant’s motion to suppress all evidence resulting from the arrest, including the breathalyzer test, the observations during booking, and the sobriety tests conducted at the station. The judge did not *72 suppress the police officer’s prearrest observations and did not dismiss the case.
1.
Legality of the arrest.
Generally, a police officer is powerless to make a warrantless arrest outside the boundaries of the governmental unit by which he was appointed.
Commonwealth
v.
Grise,
The Commonwealth argues that, despite the fact that the officer was pursuing the defendant across town lines because of a nonarrestable traffic violation,
3
the statute nonetheless allowed the officer to arrest the defendant in Framingham. The Commonwealth suggests that the officer need not have suspected that the defendant was driving under the influence at the time he followed the defendant into Framingham. In our view, the statute cannot be read reasonably to mean that an officer need not know that an arrestable offense has been committed in his presence in order to pursue the suspect in another jurisdiction. See
Attorney Gen.
v.
School Comm. of Essex,
2. Legality of the stop. The defendant claims that Officer Geissler acted without statutory authority when he stopped the defendant in Framingham. 5 We agree. A police officer’s authority is limited to the territorial jurisdiction of his appointment, barring a statutory exception. See Commonwealth v. Harris, supra at 168-169. The Commonwealth argues that G. L. c. 90C, § 2, implicitly grants police officers the authority to make an extraterritorial stop. That statute governs the issuance of citations for automobile law viola *74 tions. Section 2 provides, in part: “A failure to give a copy of the citation to the violator at the time and place of the violation shall constitute a defense in any court proceeding for such violation, except where the violator could not have been stopped or where additional time was reasonably necessary to determine the nature of the violation or the identity of the violator, or where the court finds that a circumstance, not inconsistent with the purpose of this section to create a uniform, simplified and non-criminal method for disposing of automobile law violations, justifies the failure.” The Commonwealth argues that the Legislature intended a police officer who observes an automobile violation in his jurisdiction to have the authority to pursue that automobile into the next city or town and to stop it there for the purpose of delivering a citation to the violator.
Nowhere in c. 90C is there any provision expanding the territorial authority of police officers. Contrary to the assertions of the Commonwealth, one “circumstance . .. justifying the failure” to give a citation is the lack of the authority of a police officer to stop an automobile in a neighboring jurisdiction. The statute’s provision for delivery or mailing of the citation to a violator’s home address, in the event of a driver’s failure to stop, indicates that a police officer has no authority to stop a motorist outside his territorial jurisdiction.
Additionally, we observe the following. General Laws c. 90, § 21 (1988 ed.), which gives a police officer authority to make warrantless arrests of individuals under the influence of intoxicating substances, does not expand the territorial powers of that police officer. Commonwealth v. Grise, supra. Similarly, G. L. c. 90C, § 2, while allowing a police officer to stop a motorist in order to issue a citation, contains no provision giving the officer additional authority to make an extraterritorial stop. Last, the Legislature did not include in G. L. c. 41, § 98A, any authority for an extraterritorial stop following the fresh pursuit of a person who commits a civil traffic violation.
The Commonwealth, in arguing that the Legislature intended to give police officers authority to make extraterrito *75 rial stops, cites a number of statutes which broaden police officers’ territorial authority. See, e.g., G. L. c. 41, § 95 (1988 ed.) (extraterritorial authority to execute arrest warrants); G. L. c. 41, § 98 (1988 ed.) (extraterritorial authority to carry weapons); G. L. c. 41, § 98A (extraterritorial fresh pursuit for arrestable offenses). Rather than implying that the Legislature intended to give the police the authority to make extraterritorial stops, these statutes demonstrate that the Legislature knows how to expand the extraterritorial authority of the police when it thinks it fit to do so. The Legislature has chosen not to provide the police with extraterritorial authority to make stops for traffic violations. If it wishes to modify that judgment, it may do so.
3.
Disposition.
The police officer in this case acted without statutory or common law authority both when he stopped the defendant and when he arrested him. Our case law supports exclusion of evidence when such conduct prejudices the defendant. See
Commonwealth
v.
Grise,
The District Court judge was correct in suppressing all evidence flowing from the arrest. Because of our conclusion that the extraterritorial stop was also improper, the fruits of the stop should also have been suppressed.
*76 The order of the court is accordingly affirmed in part and reversed in part.
So ordered
Notes
The defendant was taken to the Natick station for booking even though Framingham police had arrived at the scene. In Natick, the complaints issued against the defendant were for operating a motor vehicle while under the influence of an intoxicating beverage, G. L. c. 90, § 24 (1) (a)(1988 ed.) (a criminal violation), and for failure to stop for a red light, G. L. c. 90C, § 2 (1988 ed.) (a civil infraction).
The statute also provides: “Said officer may return any person so arrested to the jurisdiction wherein said offence was committed. Nothing contained in this section shall be construed as limiting the powers of a police officer to make arrests and in so far as possible this section shall be deemed to be declaratory of the common law of the commonwealth.” G. L. c. 41, § 98A.
Passing through a red light, a civil traffic infraction, is not an arrestable offense. See G. L. c. 90C, § 2.
The out-of-State cases dealing with this particular issue indicate no clear trend. Compare
Wenatchee
v.
Durham,
This issue was decided against the defendant by the motion judge, who refused to suppress any prearrest evidence which resulted from the stop. Ordinarily, a defendant may not pursue an interlocutory appeal of a denial of a motion to suppress. See
Commonwealth
v.
Mottola,
