The defendant Reynolds, indicted for receiving stolen goods and other offenses, moved in the Superior *143 Court before trial to suppress evidence (the alleged stolen property) seized by the Commonwealth pursuant to a search warrant which had been issued by a District Court clerk on the affidavit of a police officer. Facts bearing on the motion to suppress were stipulated between the Commonwealth and the defendant. After consideration, a judge of the Superior Court denied the motion and, acting under G. L. c. 278, § 30A, reported the following question to thе Appeals Court (whence we took it for direct review): “Should a motion to suppress evidence be allowed when such evidence was obtained upon an affidavit containing misstatements?” We shall first discuss the question more or less in the abstract, and then address ourselves to the рarticular case.
1. After the Supreme Court of the United States had held in
Weeks
and
Mapp
1
that evidence obtained in violation of the Fourth Amendment was subject to exclusion at trial, and after
Spinelli, Aguilar,
and Brinegar
2
had described the requirements for a finding of “probable cause” under the amendment, it might have been foretold that courts would begin to question a certain rule restricting attacks on the validity of search warrants. By that rule the allegations of an affidavit supporting a warrant and purporting to show probable cause could be tested judicially only for their surface sufficiency; in no event could the allegations be pierced and their truth inquired into. See Annot., 5 A.L.B.2d 394 (1949). The Supreme Court intimated in
Rugendorf
v.
United States,
*144
In defense of the rule, it may be pointed out that the evidence sought to be suppressed will be in every case material to proof of guilt, otherwise the defendant would not be at pains to try to put it beyond consideration of the triers. An affiant, usually a police officer, will have submitted particulars on oath purporting to establish probable cause. A disinterested magistrate must have examined the allegations and found them sufficient on their face and at least not transparently false. Judicial review of the facts in suppression hearings might thus be thought an unessential if not a perverse procedure for which a price in time and effort has to be paid. See
State
v.
Petillo,
*145
It has been held in the Federal circuits generally,
4
and in some State courts
5
(with others opposed
6
), that the truth of affidavits is not altogether beyond inquiry at suppression hearings, that there are situations in which findings of falsity should result in invalidation of thе corresponding warrants and exclusion of the evidence obtained. Differences arise, however, as to the nature of these situations, which is another way of saying that there remains the question how far the postulated purposes of an exclusionary rule — deterrencе of official misconduct, protection of the integrity of the legal process — are to be pursued despite the price paid for the exercise. See
United States
v.
Halsey,
Falsity in the affidavit can come about through intention, recklessness, negligencе, or innocent mistake; the false information may be indispensable to a showing of probable cause or fall short of that. The case for suppression is felt to be strongest where material false information was intentionally introduced into the affidavit by an official acting as аffiant. 7 There is diminished perceived ground for suppression as the factors of the blameworthiness of the official and the importance of the information shade off; but reasoned authority exists for suppression in some situations of intentional nonmaterial, and negligent material, misstatements. 8
*147
Such remarks on the subject as this court has made in previous opinions intimate agreement with the proposition mentioned above as least disputable (and perhaps lend support for a somewhat broader proposition). Thus we have twice been willing to assume arguendo that “a deliberate misrepresentation in an affidavit will render a search warrant invalid.”
Commonwealth
v.
Murray, 359
Mass. 541, 548 (1971).
Commonwealth
v.
Perez,
2. We turn to the details of the present case as they emerge from the report. Prеsented to the clerk of the First District Court of Bristol on August 22, 1973, was an affidavit dated the same day of Raymond C. McKearney, a Rehoboth police officer. He swore that on the previous day he had been informed by a detective of the Pawtucket, Rhode Island, police department that he, the detective, had received information from a “reliable informant” that two truckloads of assorted lumber, stolen from the Arland Lumber Company in Pawtucket, were in the possession of Bruce J. Reynolds of Rehoboth. McKearney swore, further, that Norman Bisson, general manager of the company, had *148 viewed this lumber, all pre-cut, from Rocky Hill Road, Rehoboth. “The lumber is to the rear of Bruce Reynolds home [82 Rocky Hill Road], and Mr. Bisson identified the covering on the lumber and also some of the lumber as that which was stolen from Arland Lumber Co. on August 20, 1973.” On the basis of these averments, the clerk issued a search warrant on August 22. (It is unnecessary to state the exact terms of the warrant or of the return.)
According to the stipulation of the parties addressed to the truth of the averments of the affidavit, Bisson and McKearney were passengers in a car that was drivеn past the Reynolds house several times on August 21. Bisson did not observe any pre-cut lumber or any special factory covering on the lumber, and had not told the police that he had. He was able to observe a pile of black sheeting material on the Reynolds property аnd identified that as part of the material stolen from his company. After the drive past the Reynolds house, McKearney conferred with the chief of police of Rehoboth who “advised Officer McKearney as to the wording of the affidavit” that was presented as the basis for the issuаnce of the warrant.
We observe, first, that no support can be derived for a finding of probable cause from the allegations of the affidavit regarding information received from the Pawtucket detective. The detective’s statement to McKearney stands on the unnamed infоrmant’s communication to the detective, but nothing is offered to substantiate the conclusion that the informant was “reliable.” See
Commonwealth
v.
Stevens,
There is one statement in the stipulation that has no counterpart in the affidavit, namely, that Bisson identified some black sheeting material as stolen. This statement cannot support the warrant because, being absent from the affidavit, it was not before the clerk who issued the warrant.
*149
See
Commonwealth
v.
Causey,
3. The stipulation, representing, as we may suppose, the lowest common denominator of anticipated testimony, is not full enough to base a judgment whether the behavior of the police was blameworthy or otherwise. Characterization of their conduct on the basis of the stipulation was not attempted by the judge, nor will it be by us here. But such an appraisal is important to decision, as point 1 shows. Therefore the matter will be rеmanded to the Superior Court for the taking of proof to permit the judge to reach a conclusion based on appropriately detailed findings. We can say now that if the judge should conclude on a preponderance of the evidence that the misstatements in thе affidavit were intentional (they were certainly material), he should suppress the evidence obtained under the warrant. If he concludes that there was mere inadvertence without negligence, he should refuse to suppress. If his conclusion lies between these polar categories, he may return the matter directly to this court. In this troublesome area much may turn on detail, and we would be loath to formulate our views except with the benefit of a concrete, complete record on which a trial judge has had a chance to reflect. 10
*150
We think the burden of persuasion should be on the defendant to justify suppression based on misstatements in an affidavit underlying a warrant. See
People
v.
Alfinito,
With respect to procedure, the present status of the case is such that we do not face herе the problem how to screen out plainly unmeritorious applications. We are prepared to say, however, that we join in the general view that the defendant usually should be obliged to make a preliminary showing, which ordinarily will be in affidavit form, that he has a case worthy of full hearing; otherwise hearing should be denied. 11 (It can be anticipated that there may be special difficulties, which will need to be worked out case by case, where a challenge is sought to be put to an affidavit in which the affiant has relied on information supplied by an unnamed informant. 12 )
It has not escaped our attention that the exclusionary doctrine of
Weeks
and
Mapp
has been subjected to strong
*151
attack
13
(and been strongly defended
14
) and that it has been somewhat narrowed or weakened by recent opinions of the Supreme Court.
Stone
v.
Powell,
The case is remanded to the Superior Court for proceedings consistent with this opinion.
So ordered.
Notes
Weeks
v.
United States,
Spinelli
v.
United States,
The Court may face the question in reviewing
Franks
v.
State,
See
United States
v.
Collins,
State
v.
Davenport,
See
State
v.
Sabari,
A variety of wordings have been used to describe the extreme category of affiant insincerity. See
United States
v.
Belculfine,
Many courts have gone to the point of applying an exclusionary rule to cases of reckless material misstatements, with recklessness defined at times as a lack of reasonable grounds for believing the averments to be true. See
United States
v.
Lee, supra; United States
v.
Luna, supra; United States
v.
Marihart,
That suppression might follow from negligent аs well as intentional misrepresentation has been supported on the ground of deterrence, and also on a simple analogy to the law of warrantless search. When war *147 rantless searches are judicially reviewed by reference to a standard which echoes thе constitutional language of reasonableness (“The right of the people to be secure in their persons, houses, papers and effects, against unreasonable searches and seizures”), it may be contended that a like standard should apply in judicial scrutiny of the statements offered to procure the issuance of a warrant. See Theodor v. Superior Court, supra at 98-100.
As indicated in the text below, the case as it now stands does not admit of a characterization of the conduct of the Commonwealth through the police. In the absence of a complete record, it is not possible to evaluate the strength of any intimation that when it appeared that Bisson’s identification of the black sheeting would be of dubious probative value, no mention of this was made in the affidavit, and reference to pre-cut lumber and special covering was thеn inserted.
Similar reluctance to make a pronouncement in this field beyond the necessities of the particular case appears in
United States
v.
Belculfine,
United States
v.
Harris,
See
McCray
v.
Illinois,
Bivens
v.
Six Unknown Named Agents of Fed. Bureau of Narcotics,
See
United States
v.
Peltier,
See
Selectmen of Framingham
v.
Municipal Court of the City of Boston,
