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SJC-12510

COMMONWEALTH vs. JOSE L. ARIAS.

Essex. September 7, 2018. - March 15, 2019.

Present: Gants, C.J., Lenk, Gaziano, & Lowy, JJ.

Constitutional Law, Search and seizure, Probable cause. Search 

and Seizure, Probable cause, Exigent circumstances, 

Emergency, Multiple occupancy building, Protective sweep, 

Plain view. Probable Cause. Practice, Criminal, Motion to 

suppress, Interlocutory appeal, Appeal by Commonwealth.

Evidence, Informer. Witness, Police informer. Controlled 

Substances.

Indictments found and returned in the Superior Court 

Department on April 14, 2014.

A pretrial motion to suppress evidence was heard by MaryLou Rup, J.

An application for leave to prosecute an interlocutory 

appeal was allowed by Hines, J., in the Supreme Judicial Court 

for the county of Suffolk, and the appeal was reported by her to 

the Appeals Court. After review by the Appeals Court, the 

Supreme Judicial Court granted leave to obtain further appellate 

review.

Esther J. Horwich (Stephen J. Wright also present) for the 

defendant.

Kenneth E. Steinfield, Assistant District Attorney, for the 

Commonwealth.
2

David R. Rangaviz, Committee for Public Counsel Services,

for Committee for Public Counsel Services, amicus curiae, 

submitted a brief.

GAZIANO, J. In this case, we confront the scope of two 

exceptions to the warrant requirement that have resulted in some 

confusion in previous jurisprudence in the Commonwealth: the 

emergency aid exception and the exigent circumstances exception.1

1. Background. a. Facts. We summarize the facts found 

by the motion judge following an evidentiary hearing on the 

defendant's motion to suppress, supplemented by uncontroverted 

and undisputed facts in the record that were implicitly credited 

by the judge and that do not detract from the judge's ultimate 

findings. See Commonwealth v. Jones-Pannell, 472 Mass. 429, 431 

(2015). We reserve some details for later discussion.

On the evening of March 4, 2014, the Lawrence police 

department received a tip from an unnamed 911 caller.2 The 

caller stated that she was "coming down the street" when she saw 

two "Spanish guys" "with a gun . . . going up to the building"

located at "7 Royal Street" in a residential neighborhood in 

Lawrence. The caller stated that "they . . . had a hat on," and 

 

1 We acknowledge the amicus brief submitted by the Committee 

for Public Counsel Services.

2 The record does not contain precise times concerning when 

the 911 call occurred or when officers responded to the scene. 

Notably, when the officers responded, they were working the 

"night shift," which began at 5 P.M. and ended at 1 A.M.
3

were wearing "a jacket and a coat," one of which "was gr[a]y and 

the other was black." The caller "heard . . . one of them load 

the gun," and saw the men enter the building. The caller said

that "there's always a little movement in that building," and 

acknowledged that she was "not really sure what's going on." In 

addition, the caller stated that she was new to the 

neighborhood, and that she had not seen the men previously. She 

provided the dispatcher with her home address, and the 

dispatcher indicated to the caller that he was aware of the 

caller's telephone number.

A dispatcher subsequently issued the following report: 

"Any detective or any available north car [near the specified 

address], caller said she saw two Hispanic males enter a house, 

one in a gray jacket, one in a black jacket, the male was 

loading gun, was loading a cli[p] to a handgun."3

The motion judge credited that, during the general period 

in which the 911 call was made, the Lawrence police department 

was investigating a "rash" of "home invasions" believed to be 

the work of a "crew" from New York. The judge noted, however, 

that the evidence did not indicate "how recently or where" the 

home invasions had occurred, or if any home invasion had 

 

3 The judge found that both the 911 caller and the police 

dispatcher "provided very general descriptions" of the men who 

entered the building.
4

"occurred in the immediate vicinity or neighbor[hood] of" the 

particular street.

Multiple police officers responded to the dispatch. The 

address given was one of two numbers associated with a four-unit

apartment building. The building had a single front door, 

marked with the number "5" on the right side of the door and the 

number "7" on the left side of the door. The building contained 

two apartments on the ground floor, numbered "5A" and "7A," and 

two apartments on the upper floor, numbered "5B" and "7B." At

the rear of the building, there was a porch with two entrances.

Sergeant Michael Simard of the Lawrence police department

was the supervising patrol sergeant that evening. He arrived at 

the scene in a marked cruiser and was wearing a uniform. Simard 

saw no one outside the building. He and a number of other 

officers monitored the front entrance.

Sergeant Joseph Cerullo of the Lawrence police department's 

special operations division arrived at the scene in a marked 

cruiser; he, too, was wearing a uniform and a badge.4 Cerullo

and four other officers, including two members of the canine 

unit of the Essex County sheriff's department, moved to the rear 

of the building.

 

4 In his role with the special operations division, Sergeant 

Joseph Cerullo was responsible for emergency responses.
5

At the front of the building, Simard spoke to residents of 

unit 7A, the first-floor apartment located across the hall from 

unit 5A. The residents of unit 7A denied seeing or hearing 

anything out of the ordinary, and said that they did not know 

who lived in unit 5A. The residents did describe, however, the 

"layout of the apartment [at unit 5A] as far as what door leads 

to where." Simard commented that the residents of unit 7A were 

scared because of the "[fifteen] police officers with their guns 

drawn." Simard also stated that, except for the residents of 

unit 7A, no residents of the building appeared to be at home.

After obtaining the telephone number of the 911 caller, 

Simard spoke with her by telephone.5 The caller told Simard that 

 

5 The judge found that the record did not make clear whether 

Sergeant Michael Simard spoke first to the residents of unit 7A 

or to the 911 caller. We analyze the judge's findings as to 

this point based on the record that was before her, and we do 

not address later-discovered evidence that the judge did not 

consider. Were we to consider this evidence, it would not 

change the result we reach.

At the hearing, the parties stipulated to the admission of 

a compact disc (CD) that contained audio recordings captured on 

a single audio track. The recordings were of the initial 911 

call and the dispatch provided to responding officers. The 

judge listened to those recordings; she also was provided a copy 

of a CD that contained only those recordings. In its brief to 

the Appeals Court, however, the Commonwealth submitted a CD that 

contained additional audio recordings of police communications 

that had not been before the motion judge, and that were not 

transcribed in the filings in the Superior Court or on appeal. 

In particular, one of the recordings contains a telephone 

conversation between an employee of the Lawrence police 

department and the 911 caller that highlights a discrepancy as 

to when Simard spoke with the 911 caller. The judge made no 
6

she had seen three males whom she did not recognize talking on 

the front step of the building located at "5-7" on that street. 

The caller stated that she had heard the sound of a "rack" being 

pulled back on a semiautomatic handgun,6 a sound she recognized 

because she was "from Lawrence." According to Simard, the 

caller did not see a firearm. The caller was nervous, and was 

aware of recent armed robberies "in the area." The judge found 

that the "officers at the scene learned the above-described 

information within minutes of their arrival."7

The caller told Simard that the men likely had a key to the 

building because they entered the front door "easily." Cerullo 

 

findings as to that discrepancy, evidence of which was not 

before her.

6 "Racking" a handgun involves pulling the slide back to 

load a round into the chamber. See Commonwealth v. Arias, 92 

Mass. App. Ct. 439, 447 n.9 (2017). Although the officers did 

not determine whether anyone living in the building was licensed 

to carry a firearm, the judge credited testimony that a firearms 

license check would have taken a significant amount of time.

7 Cerullo testified that he and Simard "convers[ed] back and 

forth" and that Simard shared information he had learned from 

the 911 caller. The judge found that "Cerullo and Simard 

discussed the information." According to Cerullo, Simard's 

"knowledge from the [911] caller was enough for [Cerullo] to 

make [his] determination to enter the building" because "[t]he 

knowledge of one would be the knowledge of all." It does not 

appear, however, that Simard shared all the information he had 

learned from the 911 caller. Cerullo testified that he 

"possibly heard" that there were "three individuals out front" 

of the building, as the 911 caller ultimately told Simard. He 

testified also that he was not made aware that those individuals 

likely had a key to the building. In any event, Simard, not 

Cerullo, ultimately made the decision to enter unit 5A without a 

warrant.
7

acknowledged that he and the other officers did not consider 

whether the men who allegedly entered the building with a 

firearm were residents of the building.

At the rear of the building, Cerullo observed a Hispanic 

male leave the building from the left rear door. The man had 

facial hair and was "wearing a black and gray sweater." He was 

identified at the evidentiary hearing as "Wascar Bievenido 

Guerrero Diaz."

With his firearm drawn, Cerullo shouted, "Lawrence Police. 

Show me your hands." From the front of the building, Simard was 

able to hear Cerullo. Diaz appeared "shocked" and "quickly went 

back inside" the building, "closing the door behind him." 

Cerullo and another officer attempted to enter the building 

through the door Diaz had used, but, as the judge determined, 

they "found it locked."8 According to Cerullo, the door was 

associated with apartment "number 5." Cerullo did not specify 

whether he was referring to apartment 5A, 5B, or both.

Cerullo moved to the front of the building to discuss the 

situation with Simard, while four officers remained at the rear 

of the building. Focusing their attention on unit 5A, Cerullo

 

8 The judge did not find that Diaz locked the door to 

prevent officers from entering the building.
8

and Simard made the decision to enter that unit without a 

warrant.9

Within approximately three to eight minutes after police 

arrived at the scene, Cerullo "entered the front door 

forcefully," and then led a number of officers through the front 

door of the building and into unit 5A. Conducting a "protective 

sweep" for any injured persons and the Hispanic male he had seen

earlier at the rear of the building, Cerullo moved through the 

living room toward the rear of the building. Other officers 

searched different areas of the apartment. They did not find 

any people, but they did observe in plain view what appeared to 

be illegal narcotics, a scale, and plastic bags strewn on the 

floor. The officers did not seize anything at that point.

At the rear of the apartment, Cerullo encountered a door 

leading to a hallway outside unit 5A. In the hallway, he saw 

another door. The officers believed that this was the door that

Diaz had used minutes earlier. Cerullo also saw a stairway 

leading up to unit 5B and down to a basement; a light was on in 

the basement. After confirming the absence of any people inside

unit 5A, Cerullo, other officers, and several canine unit dogs 

searched the basement; they found and arrested three 

 

9 The judge found that there was no basis for the officers 

to have focused their attention on unit 5A. In addition, the 

judge noted that the officers were unaware of anyone who lived 

in that apartment.
9

individuals. They did not search anywhere else in the building

for the suspected home invaders.

Based on observations made during the warrantless search of 

unit 5A, officers obtained a search warrant. Pursuant to the 

warrant, they searched unit 5A again and seized items from the 

apartment.

b. Procedural history. The defendant filed a motion to 

suppress evidence seized pursuant to the warrant, on the ground 

that the warrant was predicated on observations made during an 

unconstitutional search. Following an evidentiary hearing, a 

Superior Court judge allowed the motion.10 The Commonwealth 

filed a petition seeking leave to pursue an interlocutory 

appeal, and a single justice of this court allowed the appeal to 

proceed in the Appeals Court. In a split decision, a panel of 

the Appeals Court reversed the motion judge, after concluding 

that the warrantless search was permissible under the emergency 

aid doctrine. See Commonwealth v. Arias, 92 Mass. App. Ct. 439, 

449 (2017). We allowed the defendant's application for further 

appellate review.

2. Discussion. "In reviewing a ruling on a motion to

suppress, we accept the judge's subsidiary findings of fact 

 

10 Although the judge allowed the motion to suppress as to 

the defendant and a codefendant, this appeal pertains only to 

the defendant.
10

absent clear error 'but conduct an independent review of [the 

judge's] ultimate findings and conclusions of law.'" 

Commonwealth v. Cawthron, 479 Mass. 612, 616 (2018), quoting 

Commonwealth v. Scott, 440 Mass. 642, 646 (2004).

A "warrantless government search of a home is presumptively 

unreasonable under the Fourth Amendment to the United States 

Constitution and art. 14 of the Massachusetts Declaration of 

Rights." Commonwealth v. Entwistle, 463 Mass. 205, 213 (2012), 

cert. denied, 568 U.S. 1129 (2013). See Kentucky v. King, 563 

U.S. 452, 459 (2011); Brigham City v. Stuart, 547 U.S. 398, 403 

(2006). "The presumption against warrantless searches reflects 

the importance of the warrant requirement to our democratic 

society." Commonwealth v. Tyree, 455 Mass. 676, 683 (2010). 

"Under the exclusionary rule, evidence seized pursuant to an 

unreasonable search generally will be suppressed." Commonwealth

v. Tuschall, 476 Mass. 581, 584 (2017). "Warrantless searches 

may be justifiable, however, if the circumstances of the search 

fall within an established exception to the warrant 

requirement." Id.

a. Emergency aid exception. The emergency aid doctrine 

establishes one such "narrow exception to the warrant 

requirement." See Commonwealth v. Duncan, 467 Mass. 746, 754, 

cert. denied, 135 S. Ct. 224 (2014). The emergency aid 

exception applies when law enforcement officers enter a dwelling
11

to provide emergency assistance. See Commonwealth v. Snell, 428 

Mass. 766, 774, cert. denied, 527 U.S. 1010 (1999) (entry is 

reasonable under emergency aid exception when made "not to 

gather evidence of criminal activity but rather, because of an 

emergency, to respond to an immediate need for assistance"

[citation omitted]).

To fall within the narrowly construed emergency aid 

exception, "a warrantless entry and protective sweep must meet 

two strict requirements." See Commonwealth v. Peters, 453 Mass. 

818, 823 (2009). First, at the time of entry, there must be an 

objectively reasonable basis for the officers to believe that an 

emergency exists. See Entwistle, 463 Mass. at 213. Second, 

after the entry, the conduct of the officers must be reasonable 

under the circumstances, id. at 216; in other words, the search

must not exceed the scope of the emergency. See Peters, supra.

"Where these two conditions have been satisfied, warrantless 

entry into a home is permissible." Duncan, 467 Mass. at 751.

The "burden rests with the Commonwealth to demonstrate that a 

warrantless search . . . fits within the emergency aid exception 

to the warrant requirement." Entwistle, supra at 215, quoting 

Peters, supra. See Snell, 428 Mass. at 774-775.

i. Objectively reasonable belief. To meet its burden, the 

Commonwealth first must demonstrate objectively reasonable 

grounds to believe that an emergency existed at the time of 
12

entry. See Peters, 453 Mass. at 823. See also Hill v. Walsh, 

884 F.3d 16, 19 (1st Cir. 2018) (warrantless entry into dwelling 

requires "objectively reasonable basis for believing" that 

"immediate aid" is required by someone within [citation 

omitted]).

In determining whether a warrantless entry is objectively

justified, we evaluate it "in relation to the scene as it could 

appear to the officers at the time, not as it may seem to a 

scholar after the event with the benefit of leisured 

retrospective analysis" (citation omitted). Peters, 453 Mass. 

at 825. A reviewing court does not consider officers' 

subjective motivations in entering a house. See, e.g.,

Entwistle, 463 Mass. at 214. See also Michigan v. Fisher, 558 

U.S. 45, 47 (2009).

The reasonableness of an entry is evaluated under the 

totality of the circumstances. Compare Tuschall, 476 Mass. 

at 585-588 (warrantless entry was unreasonable when fumes 

adversely affected neighbor and her pet, but did not threaten

imminent injury, death, or explosion, and there was no 

indication anyone inside dwelling required emergency 

assistance), with Commonwealth v. Townsend, 453 Mass. 413, 426

(2009) (warrantless entry was reasonable where dwelling was

victim's last known location, her vehicle was parked outside, 

she had not been seen or heard from in days, and she had missed
13

scheduled visits with her children and her roommate). See, 

e.g., Entwistle, 463 Mass. at 210, 215-216 (warrantless entry 

was reasonable where victim had not been seen or heard from in 

days, had uncharacteristically missed multiple appointments with 

family and friends, and victim's dog could be heard barking 

inside house); Snell, 428 Mass. at 768-769, 775 (warrantless 

entry was reasonable where victim's vehicle remained parked 

outside house for multiple days, victim had not answered 

multiple telephone calls from her children, and victim had not 

called to wish her son's wife happy birthday).

Entering officers "do not need ironclad proof of 'a likely 

serious, life-threatening' injury," Entwistle, 463 Mass. at 214, 

quoting Fisher, 558 U.S. at 49, in order for a warrantless entry 

to be reasonable under the circumstances. In addition, because 

the entry is made "to prevent harm stemming from a dangerous 

condition, not to investigate criminal activity," a reviewing 

court "does not require that police have probable cause that a 

crime has been committed." Tuschall, 476 Mass. at 585. See

Duncan, 467 Mass. at 750; Hill, 884 F.3d at 23. It is 

sufficient where the totality of the circumstances demonstrates

objectively reasonable grounds to believe that emergency 

assistance is needed to prevent imminent physical harm, to 

provide assistance to one who is injured, or to protect life or, 
14

in some circumstances, property.11 See, e.g., Entwistle, supra

at 214, 216.

ii. Reasonableness of police conduct inside the dwelling. 

To rely upon the emergency aid doctrine, the Commonwealth also 

must demonstrate that the conduct of the officers after they 

entered the premises was reasonable under the circumstances. 

See Entwistle, 463 Mass. at 216. To be reasonable, the 

warrantless conduct of the officers inside the dwelling must be 

"strictly circumscribed" by the circumstances of the emergency 

that justified entry. See Commonwealth v. Lewin (No. 1), 407 

Mass. 617, 622 (1990), quoting Mincey v. Arizona, 437 U.S. 385, 

393 (1978). Thus, a protective sweep made pursuant to the 

emergency aid exception "must be limited in scope to its 

purpose," Peters, 453 Mass. at 823, e.g., to preventing imminent 

harm, protecting life or property,12 or providing aid to one who 

is injured.

In addition, to be reasonable under the emergency aid 

doctrine, the officers' conduct after entry "may not be expanded 

 

11 In Michigan v. Tyler, 436 U.S. 499 (1978), the United 

States Supreme Court addressed a narrow context in which 

protection of property may support warrantless entry pursuant to 

the emergency aid exception. There, the Court held that 

firefighters who enter a building to extinguish a fire 

"require[] no warrant, and that once in the building, [they] may 

remain there for a reasonable time to investigate the cause of 

the blaze." Id. at 511.

12 See note 11, supra.
15

into a general search for evidence of criminal activity." See 

Entwistle, 463 Mass. at 217, citing Arizona v. Hicks, 480 U.S. 

321, 325 (1987). See also Lewin (No. 1), 407 Mass. at 622. 

Therefore, if, after entry, officers no longer have an 

objectively reasonable basis to believe that an emergency 

exists, it is unreasonable to continue searching. See Mincey, 

437 U.S. at 393 (warrantless search was unreasonable when 

conducted after officers had located all persons in dwelling 

during prior protective sweep); Commonwealth v. Kaeppeler, 473

Mass. 396, 403 (2015) ("continued police presence in the 

defendant's home without his consent after he was transported to 

the hospital for medical treatment and the subsequent seizure of 

[evidence in plain view] was unreasonable," because emergency 

concerning "the defendant's well-being had ended," and evidence 

was seized for "an investigative purpose"); Peters, 453 Mass. 

at 820 (warrantless search of dwelling was unconstitutional 

after protective sweep eliminated objectively reasonable basis 

to believe that emergency existed).

After completing a protective sweep, however, if officers 

continue to have an objectively reasonable basis to believe that 

an emergency exists, a subsequent sweep that is limited to the 

scope of the emergency may be justified. See Entwistle, 463 

Mass. at 215-219 (two instances of law enforcement entry coupled

with protective sweeps were justified under emergency aid 
16

exception, because each was supported by objectively reasonable 

bases to believe that emergency existed, and officers' conduct 

during each sweep was reasonably limited to scope of emergency 

at hand); Peters, 453 Mass. at 825 ("We do not declare a 'one 

sweep rule'" . . .).

Undoubtedly, when officers have an objectively reasonable 

basis to believe that an emergency exists, and they reasonably 

circumscribe the scope of their conduct after entry, "[e]vidence 

observed in plain view may be seized," Peters, 453 Mass. at 823, 

provided that the officers "have not violated the Fourth 

Amendment in arriving at the spot from which the observation of 

the evidence is made," King, 563 U.S. at 463; the "incriminating 

character" of the evidence is "immediately apparent" (citation 

omitted), Kaeppeler, 473 Mass. at 405; and the evidence actually 

is in plain view. See, e.g., Hicks, 480 U.S. at 324-325, 328

("a truly cursory inspection -- one that involves merely looking 

at what is already exposed to view, without disturbing it -- is 

not a 'search' for Fourth Amendment purposes," but disturbing or 

moving objects in plain view constitutes "a 'search'" for which 

warrant is required); Entwistle, 463 Mass. at 217 (observation 

of content of printed bill fell within scope of emergency aid 

exception where "[t]he officer did not open a bill still in its 

envelope or search for it in a file or drawer; he merely read 
17

what was in plain view from an already opened bill that lay on 

the kitchen table").

With these considerations in mind, we turn to the search at 

issue.

iii. Initial search of unit 5A and basement. The 

defendant maintains that the officers who entered unit 5A and 

the basement without a warrant lacked objectively reasonable 

grounds to believe that an emergency existed. The Commonwealth, 

for its part, acknowledges an "absence of precedent" justifying

the officers' warrantless entry under the emergency aid 

doctrine.

As the motion judge noted, the "Commonwealth's claim that 

the officers had reason for concern that an armed man was 

present inside the apartment building is not completely without 

merit." "[P]olice need not wait for screams from within in 

order to fear for the safety of occupants or themselves."

United States v. Lenoir, 318 F.3d 725, 730 (7th Cir.), cert. 

denied, 540 U.S. 841 (2003). Entry into unit 5A pursuant to the 

emergency aid exception, however, required an objectively 

reasonable basis to believe that an emergency existed. See, 

e.g., Fisher, 558 U.S. at 47; Tuschall, 476 Mass. at 585. The 

totality of the circumstances at the time of the entry into 

unit 5A did not support such a basis.
18

When the officers arrived at the scene in response to the 

911 call, they saw and heard no signs of disturbance, and 

detected no signs of forced entry. To the contrary, they 

observed that the doors to the building, and to unit 5A, were 

closed and intact. Moreover, when Simard spoke with the 

911 caller, she said that the men had entered the building 

"easily," because they likely had a key. The officers

interviewed residents of unit 7A and learned that the residents, 

too, had seen and heard nothing suspicious or out of the 

ordinary. No one else informed the officers of any commotion, 

noises, or sounds coming from unit 5A. As the motion judge 

found, the officers had no knowledge of any residents or victims 

inside unit 5A, and the only residents of any unit the officers 

knew were present were the unharmed residents of unit 7A.

The fact that Diaz was observed at the back of the building

does not transform the situation into an emergency. There was 

no indication that he was injured, in need of emergency 

assistance, armed, or about to harm others, or that he had 

harmed others.

Regardless of whether the officers had sincerely held 

beliefs as to the existence of an armed home invasion or hostage 

situation, their subjective beliefs at the scene cannot justify 

a search under the emergency aid exception. See, e.g., Stuart, 

547 U.S. at 404; Entwistle, 463 Mass. at 214. The totality of 
19

the circumstances at the time of entry here did not establish a 

reasonable basis to believe that an emergency existed in 

unit 5A.13 See Tuschall, 476 Mass. at 585-587. Therefore, the 

warrantless search was not justified under the emergency aid 

exception.

Our analysis does not end there, however. We turn to 

consider whether the entry was justified for some other reason, 

i.e., under the probable cause and exigent circumstances 

exception.

b. Probable cause and exigent circumstances exception. 

The judge concluded that, under the exigent circumstances 

doctrine, the facts confronting the officers did not establish 

the existence of an exigency, or probable cause of an armed home 

invasion or hostage situation in progress.

Pursuant to both art. 14 and the Fourth Amendment, the 

exigent circumstances doctrine establishes another "wellrecognized," King, 563 U.S. at 460, yet "narrow" exception to 

the warrant requirement, see Tyree, 455 Mass. at 691. See also

 

13 As to the second prong of the emergency aid exception, 

the reasonableness of the scope of the search, the judge found 

that "credible evidence showed that the police conducted only a 

limited protective sweep." The defendant argues, however, that 

the search of the basement was unreasonable, as the officers had 

found no sign of an emergency in unit 5A. Because the officers 

lacked an objectively reasonable basis to believe that an 

emergency existed anywhere in the building, a protective sweep 

was unjustifiable under the emergency aid doctrine, regardless 

of the scope of that sweep.
20

Commonwealth v. Young, 382 Mass. 448, 456 (1981) ("Exigencies 

which may justify a procedure without warrant are a narrow 

category and must be established by the Commonwealth . . ."); 

Commonwealth v. Forde, 367 Mass. 798, 800 (1975) ("the standards 

as to exigency are strict").

"In the absence of a warrant, two conditions must be met in 

order for a nonconsensual entry to be valid" under the exigent 

circumstances doctrine: (1) "there must be probable cause" and

(2) "there must be exigent circumstances." Commonwealth v. 

DeJesus, 439 Mass. 616, 619 (2003). See Figueroa, 468 Mass. 

at 211-212. In this way, "[t]he exigent circumstances exception 

to the warrant requirement may be more appropriately denominated 

the exception for probable cause and exigent circumstances"

(emphasis in original). J.A. Grasso, Jr. & C.M. McEvoy, 

Suppression Matters Under Massachusetts Law § 14-1[a] (2017). 

See Kirk v. Louisiana, 536 U.S. 635, 638 (2002) (per curiam)

("police officers need either a warrant or probable cause plus 

exigent circumstances in order to make a lawful entry into a 

home"). Put differently, when probable cause exists to believe 

that a crime has occurred, is occurring, or will occur

imminently, warrantless entry is justified only if exigent 

circumstances also are present. See Figueroa, supra at 213. 

Conversely, without probable cause, the existence of an exigency 
21

is insufficient to permit warrantless entry into a dwelling. 

See id.

The Commonwealth "bears the burden of proof" to establish 

that a warrantless search was proper. See Young, 382 Mass. at 

456. See also Tyree, 455 Mass. at 684 ("Given the high value 

that our Federal and Massachusetts Constitutions assign to the 

warrant requirement, particularly in relation to a dwelling, we 

impose a heavy burden on the Commonwealth to justify every 

warrantless search: in the absence of consent, the Commonwealth 

must prove both probable cause to enter the dwelling and the 

existence of exigent circumstances" [footnote omitted]).

When entry is lawful under the exigent circumstances 

doctrine, "the police, in accordance with the rule of 'plain 

view,' [may] take into their possession material having apparent 

evidential connection to the criminal activity they were in 

course of investigating" (footnote omitted). Young, 382 Mass. 

at 458. See, e.g., King, 563 U.S. at 463 ("[i]t is . . . an 

essential predicate to any valid warrantless seizure of 

incriminating evidence that the officer did not violate the 

Fourth Amendment in arriving at the place from which the 

evidence could be plainly viewed" [citation omitted]); Forde,

367 Mass. at 807 ("the police had no legal justification for 

being present in the apartment and [therefore] cannot rely on 
22

the 'plain view' doctrine for a warrantless seizure of 

contraband").

We begin with the question of exigency.

i. Exigency. A warrantless entry is justified only if, in 

addition to the existence of probable cause, exigent 

circumstances are present. See Figueroa, 468 Mass. at 213. See 

also King, 563 U.S. at 470 ("Any warrantless entry based on 

exigent circumstances must, of course, be supported by a genuine 

exigency"). "[A]bsent exigent circumstances, the firm line at 

the entrance to the house . . . may not reasonably be crossed 

without a warrant" (quotations and citation omitted). See Kirk, 

536 U.S. at 635.

For exigent circumstances to exist, officers must have 

"reasonable grounds to believe that obtaining a warrant would be 

impracticable under the circumstances." Figueroa, 468 Mass. 

at 213. Impracticability arises in the context of the exigent 

circumstances doctrine when the delay caused by obtaining a 

warrant would create "a significant risk" that "the suspect may 

flee," "evidence may be destroyed," or "the safety of the police 

or others may be endangered." Id. See Tyree, 455 Mass. at 685-

691.

"In determining whether a warrantless search falls within 

the narrow exception of exigent circumstances, we consider 'the 

circumstances in their totality' . . ." (citation omitted).
23

Figueroa, 468 Mass. at 212. See King, 563 U.S. at 464. We 

review those circumstances objectively. See Young, 382 Mass. at 

456. Thus, "whether an exigency existed" is a matter "to be 

evaluated in relation to the scene as it could appear to the 

officers at the time," not as the scene might appear in 

hindsight. Id. See Figueroa, supra; DeJesus, 439 Mass. at 620 

n.3. The subjective beliefs or motives of an officer form no 

part of this inquiry. See King, supra. See also Commonwealth

v. Washington, 449 Mass. 476, 485 (2007).

In the circumstances here, for the same reasons that the 

officers lacked objectively reasonable grounds to believe that 

residents of unit 5A were in danger, pursuant to the emergency 

aid doctrine, the officers lacked a reasonable basis to believe

that they or others were at risk of imminent harm, pursuant to 

the exigent circumstances doctrine. See Figueroa, 468 Mass. 

at 213. At the scene, officers encountered no indications of 

violence or forced entry. They were unaware of any resident or 

victim inside unit 5A. Indeed, the only residents known to 

officers, those of unit 7A, were unharmed, and had neither seen 

nor heard anything suspicious. In addition, when Diaz was seen 

at the rear of the building, there was no indication that he, 

the police, or anyone else was at risk of imminent injury. We 

therefore agree with the motion judge that there was "nothing 
24

indicative of an imminent threat of danger to persons inside the 

building or to the officers."

In addition, because the building was surrounded by 

officers, there was little risk of a suspect's flight from 

within. See Figueroa, 468 Mass. at 213. Further, the record 

provides no basis for officers to have believed that evidence of 

an armed home invasion or hostage situation was at risk of 

destruction. See id. at 214.

The investigation of a crime, even a serious crime such as 

an armed home invasion, does not itself establish an exigency. 

See Mincey, 437 U.S. at 394 ("We decline to hold that the 

seriousness of the offense under investigation itself creates 

exigent circumstances of the kind that under the Fourth 

Amendment justify a warrantless search"); id. at 393 ("If the 

warrantless search of a homicide scene is reasonable, why not 

the warrantless search of the scene of a rape, a robbery, or a 

burglary? No consideration relevant to the Fourth Amendment 

suggests any point of rational limitation of such a doctrine" 

[quotation and citation omitted]).

Because officers lacked a reasonable basis to believe that 

an exigency existed in unit 5A, the warrantless search was 

impermissible. See DeJesus, 439 Mass. at 620. Even had the 

officers reasonably believed that an exigency existed, for the 

warrantless entry to be permissible, there also had to be
25

probable cause that a crime was being committed inside the 

building.

ii. Probable cause. To justify an entry into a dwelling 

pursuant to the exigent circumstances doctrine, the Commonwealth 

must demonstrate the existence of probable cause. See Tyree, 

455 Mass. at 684. "[P]robable cause exists where . . . the 

facts and circumstances within the knowledge of the police are 

enough to warrant a prudent person in believing that [an] 

individual . . . has committed or was committing an offense" 

(citation omitted). Washington, 449 Mass. at 481. Accordingly, 

"an objective test is used to determine whether probable cause 

exists." Commonwealth v. Jewett, 471 Mass. 624, 629 (2015), 

quoting Commonwealth v. Franco, 419 Mass. 635, 639 (1995).

"In dealing with probable cause . . . we deal with 

probabilities. These are not technical; they are . . . 

practical considerations of everyday life, on which reasonable 

and prudent [people], not legal technicians, act." Commonwealth

v. Cartright, 478 Mass. 273, 283 (2017), quoting Jewett, 471 

Mass. at 629. "Probable cause does not require . . . that 

police [have] resolved all their doubts." Cartright, supra, 

quoting Commonwealth v. Warren, 418 Mass. 86, 90 (1994). 

Rather, probable cause "requires more than mere suspicion but 

something less than evidence [that would be] sufficient to 
26

[sustain] a conviction." Cartright, supra, quoting Jewett, 

supra.

A. Informant's tip. Where, as here, police seek to 

establish probable cause based on an informant's tip, they must 

show, pursuant to the two-prong Aguilar-Spinelli test, both that 

the tip is grounded in a basis of knowledge, and that it is 

reliable. See Commonwealth v. Upton, 394 Mass. 363, 375 (1985). 

See also Spinelli v. United States, 393 U.S. 410 (1969); Aguilar

v. Texas, 378 U.S. 108 (1964); Commonwealth v. Alfonso A., 438 

Mass. 372, 374 (2003). With respect to informant tips, "the 

test for determining probable cause is stricter under art. 14 

. . . than under the Fourth Amendment." Upton, supra at 364.

In accordance with the Aguilar-Spinelli test, the 

Commonwealth first must establish the basis of knowledge 

underlying an informant's tip. See Alfonso A., 438 Mass. at 

374; Upton, 394 Mass. at 375. In general, the basis of 

knowledge prong is satisfied where the information provided 

springs from an informant's firsthand observations or knowledge. 

See Alfonso A., supra. In addition, where an informant's tip is 

sufficiently detailed, a reviewing court reasonably may infer 

that the informant had a direct basis of knowledge. Id. at 374-

375.

If an informant's basis of knowledge is established, to 

justify the warrantless entry, the Commonwealth then must 
27

demonstrate that the tip was credible. See Alfonso A., 438 

Mass. at 375; Upton, 394 Mass. at 375. Although a 911 caller's 

telephone number may be visible to, or determinable by, the 911 

operator, under art. 14, that alone does not demonstrate 

sufficiently the reliability of a tip. See, e.g., Commonwealth

v. Depiero, 473 Mass. 450, 454-455 (2016) (in context of 

reasonable suspicion, where showing "less rigorous" than 

probable cause is permissible, this court was "not 

inclined . . . to attribute veracity to all 911 callers"). 

Rather, "[w]hen assessing the reliability of [private 

individuals] who report apparent violations of the law, we 

accord more weight to the reliability of those who are 

identified . . . by name and address," because they are not 

protected "from the consequences of prevarication that anonymity 

would afford, and consequently may be subject to charges of 

filing false reports and risk retaliation" (citations omitted). 

Commonwealth v. Cavitt, 460 Mass. 617, 628-629 (2011). See

Depiero, supra at 455 ("The veracity test is more difficult for 

the Commonwealth to satisfy where . . . the caller was 

anonymous. Because the caller was anonymous, there could be no 

evidence regarding the caller's past reliability or reputation 

for honesty" [citation omitted]).

At the same time, "[i]t is important to recognize that 

[private individuals] who report criminal activity justifiably 
28

may be concerned for their own safety if their identity becomes 

known to the persons subsequently investigated or arrested, and 

for this reason may wish to remain anonymous." Cavitt, 460 

Mass. at 629. Such circumstances "should not stand as an 

insurmountable impediment to a favorable assessment of [the 

informant's] reliability" (citation omitted). Id. Therefore, 

an unidentified informant who nonetheless is "identifiable" by 

officers, see id., and who is aware that officers are able to 

identify him or her may receive greater credence than a fully 

anonymous informant. See, e.g., Depiero, 473 Mass. at 455 

("even if the police are able to recover the telephone number 

and identity of 911 callers, it proves absolutely nothing unless 

. . . the anonymous caller was aware of that fact. It is the 

tipster's belief in anonymity, not its reality, that will 

control his [or her] behavior" [emphasis in original; quotation 

and citation omitted]).

In addition, the reliability of a tip may be adduced from 

the extent to which an informant provides factual details. See 

Alfonso A., 438 Mass. at 375 ("it is especially important that 

the tip describe the accused's criminal activity in sufficient 

detail that the [court] may know that [it] is relying on 

something more substantial than a casual rumor . . . or an 

accusation" [citation omitted]). See also Depiero, 473 Mass. 

at 457 ("details provide a level of corroboration beyond that of 
29

'innocent' or easily obtainable facts"); Alfonso A., supra

at 376 ("While . . . detail, by itself, does not ordinarily 

suffice to establish reliability, . . . it remains a factor in 

the over-all assessment of the informant's reliability").

Each prong of the Aguilar-Spinelli test "must be separately 

considered and satisfied or supplemented in some way." Upton, 

394 Mass. at 375. If an informant's tip fails to satisfy both

prongs, other corroborating evidence, such as independent police 

corroboration, may be able to "make up for deficiencies in 

either or both prongs." Id. at 376.

B. Analysis. Our inquiry into the issue of probable cause 

begins with the 911 call. We are satisfied that the judge's 

subsidiary findings are substantiated by the record. Although 

this case presents a close question of probable cause, we

conclude, as the judge found, that the circumstances confronting 

the officers at the scene did not corroborate the caller's tip.

As to the basis of knowledge prong, we note that the 

911 caller informed the Lawrence police dispatcher that she saw 

two men "going up to the building" located at the specified 

address, and that she heard one of the men load the gun before 

he and his companion entered the building. Thus, the basis of 

the 911 caller's firsthand knowledge was apparent from the 

initial tip itself.
30

Of course, carrying a firearm is not itself a crime in the 

Commonwealth. See, e.g., Commonwealth v. Alvarado, 423 Mass. 

266, 269 (1996). But loading a handgun in public prior to 

entering a residential building does raise valid concerns about 

the possibility of imminent criminal conduct. See Commonwealth

v. Haskell, 438 Mass. 790, 793-794 (2003) (under less stringent 

standard for reasonable suspicion, as compared to standard for 

probable cause, "the act of publicly loading a handgun is an 

event that creates a reasonable suspicion that a crime may be 

about to take place"). Thus, the 911 caller claimed to have 

seen and heard what could have been criminal activity.

The more difficult question, however, is whether the 

officers had an adequate basis to conclude that the 911 caller's 

tip was reliable. In this regard, the caller provided details 

adverse to a determination of probable cause. She commented 

that the men talked calmly before entering the building, which 

they entered "easily" because they likely had a key. In 

addition, although she said that she had never seen the men 

before, she acknowledged that she was new to the neighborhood 

and was unsure of what the men were doing. The caller also 

provided details that, due to their conflicting nature, 

undermined her reliability. She initially said that two men 

entered the building, but later told Simard that three men had 

entered the building. Of course, the details provided by the 
31

caller constitute an important aspect of our assessment of her 

reliability. See Alfonso A., 438 Mass. at 376. Those details 

undercut the reliability of her tip.

Despite remaining unnamed, however, the 911 caller did give 

the dispatcher her home address. She therefore was aware that 

officers could identify her. See Depiero, 473 Mass. at 455. In 

addition, police had the ability to trace the 911 call to the 

caller's telephone number. Indeed, the dispatcher informed the 

caller that her telephone was associated with an address in 

Boston. And Simard ultimately spoke with the caller by 

telephone to discuss her observations. The 911 caller was 

therefore aware that another important component of her identity

was known to officers. We note, however, that "knowledge of the 

informant's 'identity' and 'whereabouts,'" are generally 

"not . . . adequate standing alone to confirm the informant's 

reliability." See Alfonso A., 438 Mass. at 376.

As indicated, either prong of the Aguilar-Spinelli test may 

be supplemented by corroborating evidence. See, e.g., Upton, 

394 Mass. at 375. See also Depiero, 473 Mass. at 456 ("the 

Commonwealth can . . . establish a caller's reliability through 

independent corroboration by police observation or investigation 

of the details of the information provided by the caller" 

[quotation and citation omitted]). Because the details of the 

911 caller's tip undermined her reliability, the establishment 
32

of probable cause required independent corroboration. Here, 

however, the officers discovered no corroborating evidence of 

criminal conduct; when they did not, the absence of probable 

cause became clear.

As discussed supra, Simard knew that the residents of 

unit 7A were unaware of any suspicious activity in unit 5A. 

Moreover, he was aware that the men who entered the building did 

so "easily," and that this was most likely because they had a 

key. No witness said that there had been any sound or sign of 

trouble in unit 5A; and no officer observed any sound or sign of 

struggle, violence, forced entry, or damaged property. We agree 

with the motion judge that "nothing . . . indicated that the men 

who entered" the building "did not reside there."

The judge also found that Diaz, who had facial hair and 

left the building dressed in a gray and black sweater, did not 

match the 911 caller's "very general descriptions of two 

Hispanic men" who had entered the building, one of whom wore a 

gray jacket and the other of whom wore a black jacket, and 

neither of whom had facial hair. See Commonwealth v. Warren, 

475 Mass. 530, 535-536 (2016) ("general description of the 

perpetrator and his accomplices" as "two black males 

wearing . . . 'dark clothing,' and one black male wearing a 'red 

hoodie'" made it unreasonable for police "to target the 

defendant or any other black male wearing dark clothing as a 
33

suspect"). Except for Diaz's gender and ethnicity, he did not 

match the 911 caller's general description of the men who had 

entered the multiunit apartment building earlier that evening. 

Moreover, while the Commonwealth characterizes Diaz's retreat 

into the building as evidence of guilt, "evasive conduct in the 

absence of any other information," id. at 538, is insufficient 

to support probable cause.

We acknowledge that this case presents a difficult question 

of probable cause, and that officers are at times required to 

make split-second decisions to avert violence. The racking of a 

firearm in public prior to entering a residential building is 

indeed a troubling suggestion of possible violent activity. In 

the circumstances here, however, given the absence of 

independent corroborating evidence, the reliability of the 911 

caller's testimony was insufficient to establish probable cause 

under art. 14.

Order allowing motion to

 suppress affirmed.
LOWY, J. (concurring). I agree with the court that "the 

warrantless search was not justified under the emergency aid 

exception." Ante at . I also agree that the search was not 

justified under the probable cause and exigent circumstances 

exception "[b]ecause officers lacked a reasonable basis to 

believe that an exigency existed in unit 5A." Id. at . But 

unlike the court, I am convinced that the officers had probable 

cause to enter the apartment.

"Reasonableness must be evaluated in relation to the scene 

as it could appear to the officers at the time, not as it may 

seem to a scholar after the event with the benefit of leisured 

retrospective analysis" (quotation omitted). Commonwealth v. 

Kaeppeler, 473 Mass. 396, 402-403 (2015), quoting Commonwealth

v. Townsend, 453 Mass. 413, 425-426 (2009). When police act on 

information from a private citizen, "the Commonwealth must show 

the basis of knowledge of the source of the information (the 

basis of knowledge test) and the underlying circumstances 

demonstrating that the source of the information was credible or 

the information reliable (veracity test)." Commonwealth v. 

Depiero, 473 Mass. 450, 454 (2016), quoting Commonwealth v. 

Anderson, 461 Mass. 616, 622, cert. denied, 568 U.S. 946 (2012).

Here, the court concedes that "the basis of the 911 

caller's firsthand knowledge was apparent from the initial tip 

itself." Ante at . However, the court then concludes that 
2

the caller's veracity has not been established. Id. at . I 

disagree.

The court acknowledges that the caller "was aware that 

officers could identify her" and that Sergeant Michael Simard of 

the Lawrence police department "ultimately spoke with the caller 

by telephone to discuss her observations." Ante at . It 

then concludes that "'knowledge of the informant's "identity" 

and "whereabouts,"' are generally 'not . . . adequate standing 

alone to confirm the informant's reliability.'" Id., quoting 

Commonwealth v. Alfonso A., 438 Mass. 372, 376 (2003). But this 

is not a situation in which the police merely knew the 

informant's identity. Nor is it a situation in which the 

informant knew theoretically that the police had the ability to 

contact her by telephone. Cf. Commonwealth v. Costa, 448 Mass. 

510, 517 (2007) (reliability of caller who knew "that her call 

was being recorded, and that the number she was calling from had 

been identified, . . . should have been accorded greater weight 

than that of an anonymous informant"). Here, police did contact 

the informant by telephone, and the informant responded by 

continuing to cooperate and by providing significant additional 

information. The caller also used a technical term, "racking," 

to describe what she heard, and she explained that she was 

familiar with the sound because of personal experience. See 
3

Alfonso A., supra (use of detail "remains a factor in the overall assessment of the informant's reliability").1

This reliable informant told police that she had observed 

two men with a gun enter a building at a specified address, and 

she claimed to have heard one of the men load a gun.2 It is 

unusual for an individual to load a gun on the threshold of a 

private residence. To do so in broad daylight accompanied by 

another individual only increases the unlikeliness that the 

firearm was being loaded for innocent purposes. As the court 

correctly observes, "loading a handgun in public prior to 

entering a residential building . . . raise[s] valid concerns 

 

1 I assume for purposes of my analysis, as does the court, 

that the conversation Sergeant Michael Simard of the Lawrence 

police department had with the caller took place before the 

officers entered the apartment. A recording with which we were 

provided, but to which the motion judge did not have access, 

suggests that this conversation might have occurred after the 

warrantless entry. See ante at note 5.

2 The court states that, "[a]ccording to Simard, the caller 

did not see a firearm." Ante at . But according to the 

motion judge's factual findings, which we must accept unless 

clearly erroneous, "[t]he caller reported that while coming down 

her street she observed 'two guys with a gun' at 7 Royal 

Street." That finding was not clearly erroneous. Although 

Simard testified that the caller never said she had observed a 

gun, Sergeant Joseph Cerullo of the Lawrence police department 

testified that the caller did say she had observed a gun. The 

motion judge was free to credit Cerullo's testimony over that of 

Simard. Moreover, the 911 recording, which was played in open 

court, confirms that the caller said, "I seen two guys with a 

gun."
4

about the possibility of imminent criminal conduct." Ante

at .

In addition to having reliable information from the caller 

that a gun was being loaded in public, the police also knew 

about an ongoing investigation into home invasions in Lawrence. 

And when they reached the address that the caller named, a man 

emerged from the building, only to retreat inside when an 

officer with a drawn gun told him to show his hands. The police 

tried to open the door that the man had reentered, but it was 

locked. There are many reasons why an individual might flee in 

the presence of the police. See Commonwealth v. Warren, 475 

Mass. 530, 540 (2016) (observing that black male, "when 

approached by the police, might just as easily be motivated by 

the desire to avoid the recurring indignity of being racially 

profiled as by the desire to hide criminal activity"). 

Nonetheless, it would seem to be an unusual occurrence when a 

person who is told by a police officer with a drawn weapon to 

show his hands ignores the command and reenters a residence, 

locking the door behind him. The fleeing man here, combined 

with the tip that a gun was being loaded in public and the 

knowledge of prior home invasions, gave the police probable 

cause.3

 

3 That the caller believed the men had a key to the premises 

does not alter my conclusion. It is not unusual for a crime in 
5

For the foregoing reasons, I concur.

 

a home to be perpetrated by individuals who know the victims or 

have a means peaceably to enter the premises. See Commonwealth

v. Middlemiss, 465 Mass. 627, 629 (2013) (defendant entered 

residence with key); Commonwealth v. Morgan, 460 Mass. 277, 285 

(2011) (same). See also Commonwealth v. Phap Buth, 480 Mass. 

113, 114, cert. denied, 139 S. Ct. 607 (2018) (defendant, who

had previously bought drugs from resident, entered when resident 

opened door for him); Commonwealth v. Doucette, 430 Mass. 461, 

462-463 (1999) (defendant, who had been resident's friend,

entered through unlocked door).