KAPLAN, J.

On May 7, 1973, the body of Michael J. Barry was found at Carter Street in Chelsea. He had been shot twice in the head. Five months later a Suffolk County grand jury indicted Michael B. Corradino and Alfred Abate, Jr., the former for the murder in the first degree of Barry, the latter as being accessory after the fact to the murder.

Trial of the defendants jointly, subject to G.L.c. 278, §§ 33A-33G, resulted in Corradino's being found guilty of murder in the second degree and Abate guilty as charged of being accessory after the fact.

On this appeal, each defendant urges four grounds for reversal: denial of a pre-trial motion to suppress evidence siezed during a search, under warrant, of the premises where the murder was alleged to have occurred; denial of a motion to sever the trials under the rule of Bruton v. United States, 391 U.S. 123 (1968); refusal to question the jurors as to whether they had discussed the case among themselves following an incident in the court house; and denial of a motion for a new trial based on the Commonwealth's failure to produce the complete prior criminal record of its key witness, one Carmino Robert Palermo, and also on the claimed availability of two new witnesses who could testify to the defendants' innocence. Exceptions on these points were taken and errors assigned.

1. The defendants do not challenge the sufficiency of the evidence to support the verdicts if the evidence seized under warrant was admissible, and so we turn at once to the judge's denial of the motion to suppress. In question here is only the sufficiency of the sworn application for the warrant, since the affidavits of the defendants offered at the pre-trial hearing neither contradicted the application nor suggested that the search was beyond the scope of the warrant, and the examination by the defense of Lieutenant Keating of the Chelsea police, who applied for the warrant and was the only witness called at the hearing, failed absolutely to shake any assertion in the application.

The Keating application is quite detailed and recounts the following. On Sunday, May 6, at 3 P.M., the police received an anonymous telephone call that a shooting had taken place "in" a bar known as Dorothy's Cafe. (This occupies the ground floor of a two-story building at 94-98 Park Street, Chelsea; the upstairs is reached by a separate street entrance.) Cruiser officers responded to the call and entered the bar but reported no evidence of a shooting.

Barry's body was found the following day at 6:25 A.M. Barry had been recently released after serving a sentence for armed robbery. He had a long criminal record. Lieutenant Keating knew of a link between Barry and Corradino: on April 24, Keating had arrested Corradino for unlawful possession of a revolver and found among Corradino's papers a parking ticket for a vehicle registered to Barry. Keating also knew Corradino as a daily visitor to Dorothy's Cafe. The police had long suspected that unlawful card games took place regularly on the second floor of the building housing that cafe.

On Monday the police acquired further information. From Shirley Mann, Barry's girl friend, they learned that Barry was a frequent participant, with Corradino, Abate, Lenny Senibaldi, and others, in the illegal card games at the upstairs room above Dorothy's. Miss Mann had accompanied Barry to these games on several occasions and learned that Corradino was the "operator" of the games. She said she knew that Barry had been involved in several "bad" arguments with Corradino and Abate concerning their cheating at cards: the most recent incident was on May 4, which Barry related to her; another, about a month before, between Barry and Corradino, she had herself witnessed. Miss Mann also told the police that Barry had told her he would be playing cards after 2 A.M. on May 6.

The Park Street premises were rented by (among others) Francine Corradino, whose address was the same as that of Michael Corradino.

Lieutenant Keating and other police on Monday afternoon observed Corradino in a car driven by Lenny Senibaldi parked at the intersection of Carter Street and Everett Avenue. The car proceeded to the rear of Dorothy's Cafe and parked there. When Senibaldi and Corradino observed Keating's cruiser coming up behind them, they immediately drove off.

Abate and one Sheila Ciaramello were seen by the police on Monday afternoon coming out of the street doorway leading upstairs carrying a mop and yellow pail.

In his application Monday evening, Lieutenant Keating sought a warrant for the premises 94-98 Park Street, upstairs and downstairs, to search there for a small caliber firearm and ammunition, bloodstained clothing or other paraphernalia, a bloodstained mop, and a yellow pail. A warrant issued and search was made forthwith with the telling results to be mentioned at point 2 below.

Because the evidence was seized during a search authorized by warrant, the defendants had the burden of proof on the motion to suppress. Commonwealth v. Fancy, 349 Mass. 196, 202 (1965); Commonwealth v. Antobenedetto, 366 Mass. 51, 56 (1974). Part of that burden was to show "standing" to make the challenge by demonstrating a possessory interest in the premises searched or the property seized, see Brown v. United States, 411 U.S. 223, 229 (1973), a reasonable expectation of freedom from governmental intrusion, see Katz v. United States, 389 U.S. 347, 351 (1967); Mancusi v. DeForte, 392 U.S. 364, 368-369 (1968), or "presence" at the scene at the time of search. See Jones v. United States, 362 U.S. 257, 267 (1960). The judge shortcut his consideration of the motions by finding that neither defendant had established standing; he thought it unnecessary to pass on the existence of probable cause for issuance of the warrant, the issue on which the hearing had centered. As to Abate, the judge's conclusion appears correct, for nothing was adduced on that point in the defendants' affidavits, the application for the warrant, or the testimony at the hearing. As to Corradino, there is more question. The application refers to Corradino as the "operator" of the card games, there is the statement about the rental of the premises, and Corradino's affidavit says that he was at Dorothy's Cafe when the search was conducted.

However, we need not pursue the matter of standing to the end, for we believe that the denial of both motions is supported on the plainer ground that the defendants failed to carry their burden of showing that probable cause did not exist. There is no question of witness credibility as to which the trial judge's view would be significant, and we may appraise the documents ourselves. It is not a question of the weight of any one item in the application, but the weight of the congeries of items, and we are to recall that the probable cause requirement "by its very terms recognizes the vast difference between proof of guilt beyond a reasonable doubt on the one hand and proof of probable cause to believe a fact or facts on the other hand." Commonwealth v. Stewart, 358 Mass. 747, 749 (1971). We may add that, if the police are to be encouraged to use the warrant procedure, it seems good policy to allow a certain leeway or leniency in the after-the-fact review of the sufficiency of applications for warrants. See United States v. Ventresca, 380 U.S. 102 (1965). Here the ill feeling between Corradino and Barry, the likelihood that Barry was playing cards in the room above Dorothy's with Corradino the day before his body was found, the tip about a shooting at the premises, all appearing from the application, provided the necessary "objective or concrete, substantial basis," see Commonwealth v. Pellier, 362 Mass. 621, 624-625 (1972), for the belief that the murder of Barry was committed during an illegal card game at 94-98 Park Street on May 6, and that some evidence of the crime might be found at that place. Moreover, the observation of Abate and Miss Ciaramello with mop and pail gave cause to believe that there was a danger of the removal or elimination of that evidence.

2. For purposes of the later points in this opinion we give some idea of the evidence presented at the lengthy trial that could have been credited by the jury.

In the upstairs area above Dorothy's Cafe there was a second bar room, part of which was partitioned off as a card room. The upstairs was operated on weekend evenings as an "after hours place" with liquor served and card games running from 2 A.M. until 6 or 7 A.M. or later. The defendants Corradino and Abate were both dealers in the card games and Abate in addition tended bar.

Shirley Mann, describing the incident she had witnessed a month before the murder, said Barry angrily accused Corradino of cheating, and threw chips at him when the accusation was denied; a fight was avoided only when others at the table separated the two.

It is left unclear when Michael Barry arrived upstairs on the morning of May 6, but he was present by 4 or 5 A.M. Earlier he had been at other bars where he had had several drinks.

Carmino Robert Palermo testified as an eyewitness to the shooting of Barry, alleged in the bill of particulars to have occurred in the card room "at or around 6-7 A.M." Carmino was not a patron at the after hours club but a sixty-seven year old man, an ex-boxer, who had come to clean up the bar and card room area about 6:30 A.M. as he frequently did in order to earn a few dollars. He testified to being busy cleaning in the bar area when he heard a commotion at the card tables; he went over to watch. Barry and Corradino were standing at a table. Barry said to Corradino, "You son of a bitch, you owe me money," or words to that effect. Corradino answered, "Sit down," or "Go home." Barry said, "No, I want that money, or I'll break your head." Barry appeared to Palermo to be quite drunk. Barry and Corradino were perhaps a foot apart. Another man, known to Palermo as Sonny, a cook at Dorothy's, grabbed Barry and pulled him back when he tried to lunge at Corradino. Corradino, at this moment four feet from Barry, drew something out of his pocket and fired. Palermo saw blood spurt from Barry's head. Barry slumped to the floor. Palermo and Sonny fled, as did, presumably, other patrons present. Palermo testified that when he arrived at Dorothy's Cafe downstairs on Monday, Corradino said to him, "You didn't see nothing; you don't know nothing," and Palermo agreed. Palermo soon afterwards moved to Oregon.

Corroborating the police observation of Abate and Miss Ciaramello was the testimony of Miss Ciaramello (granted immunity from prosecution) that on Monday she visited the upstairs area with Abate; he told her the cleanup man had not shown up and so the upstairs needed to be cleaned. Abate cleaned the bathroom and card area and washed the floor with disinfectant.

Following are the results of the police search as introduced at the trial. The police found stains on the upstairs bathroom sink, which on testing were determined to be blood. They also found blood on a number of items seized: a mop found downstairs, a polyethylene sheet and a piece of tissue found on the upstairs bathroom floor, a piece of linoleum from the top of the stairs to the second floor, a box found upstairs, old shoes, wood shavings, a door found in a storage room upstairs (a new door had been installed on the upstairs bathroom), and scrapings from between floor boards in the storage room. The police detected the strong odor of sylphonathol, a disinfectant, upstairs and seized a bottle of it; upon analysis it turned out to bear Abate's fingerprints.

3. The defendants' Bruton arguments, that each defendant suffered fatal prejudice through the admission of statements made by and admissible against the other, but inadmissible hearsay as to him, stands on the proposition that the judge's limiting instructions, which he was careful to give when admitting each such statement, could not be sufficiently curative, and that a severance of the joint trial was essential. The Supreme Court has made clear that not every introduction of a statement at a joint trial which is admissible against only one of the defendants, but tends to implicate the other, requires reversal. Harrington v. California, 395 U.S. 250, 253-254 (1959). Schneble v. Florida, 405 U.S. 427, 430-432 (1972). Brown v. United States, 411 U.S. 223, 231 (1973). In the Schneble case the court said, "[W]e must determine on the basis of `our own reading of the record and on what seems to us to have been the probable impact . . . on the minds of an average jury,' Harrington v. California, supra, at 254, whether . . . [the statements] were sufficiently prejudicial . . . to require a reversal. . . . In this case, we conclude that the `minds of an average jury' would not have found the State's case significantly less persuasive had . . . [the statements] been excluded. The admission into evidence of these statements, therefore, was at most harmless error." 405 U.S. at 432. In Commonwealth v. LeBlanc, 364 Mass. 1, 7-8 (1973), we said the question whether severance was required turned on the strength of the inculpation of the codefendant produced by the statement. See Commonwealth v. Devlin, 365 Mass. 149, 160 (1974).

At the pre-trial hearing, the defendants moved to sever on the basis of a summary of four statements the prosecution intended to offer which might raise Bruton problems. One was a statement by Abate to one Jean LeGallo at 2 A.M. on May 7 that "Barry and Mike had a fight the day before." The judge ruled the statement inadmissible. The other three statements were held admissible and the motion to sever denied; as each statement was introduced at trial, the motion to sever was renewed, and denied, and the judge gave his cautionary instruction.

We see no error in the admission of a statement by Abate to a Chelsea police officer during the week after the search to the effect that "[t]he police found the blood from a fight on the floor." The most direct and strongest evidence of blood on the premises came from police testimony, and whatever Abate's statement may have indicated about his own knowledge that a fight had occurred, it added nothing to the case against Corradino.

The statement, mentioned above, by Corradino to Palermo on Monday morning that Palermo "didn't see nothing" could have had no substantial prejudicial effect on Abate. Palermo's main testimony was that he saw the shooting. On this he was closely cross-examined. Corradino's statement could possibly have enhanced Palermo's credibility, and thus affected Abate, but we think it at most a detail, even if the relevant limiting instruction is overlooked.

The last "statement" consisted of testimony that Abate telephoned one Timothy Connolly, who had been upstairs on the morning of May 6, but hung up when Connolly asked about Barry. While this could hurt Abate by indicating guilty knowledge, it was, we think, without significant impact on Corradino.

4. On the last day of trial, the jury, contrary to normal practice, were brought into the court room ahead of the defendants who appeared "in custody." When counsel questioned this, the judge said the precaution was taken because on the previous evening, as the jury passed Corradino on their way out, one juror had heard Corradino say, "I did not do it. I did not do it." Counsel made no further objection to the procedure; he did not ask for interrogation of the jurors as to what they had seen, or for an instruction. Counsel sought, however, to have the jurors questioned as to whether they had discussed the case among themselves the previous evening. The judge refused the request. It is not reversible error to omit to instruct that the jury should refrain from discussing the case unless this is shown to result in prejudice, see Commonwealth v. Coleman, 366 Mass. 705, 711-712 (1975); the present situation is no more plausible for reversal. In itself, a defendant's bare statement that he is innocent does not appear hurtful to him or his codefendant. Compare Commonwealth v. Vanderpool, 367 Mass. 743, 748 (1975).

5. (a) As ground for a new trial, the defendants said they were misled about Palermo's correct name until he took the witness stand. The prosecution had named him in its list of witnesses furnished to the defense as Robert Palermo, not as Carmino Robert Palermo. But this was immaterial for both defendants knew Palermo and understood he was the person who would testify.

The defense urged also that the prosecution, either intentionally or through negligence, had not supplied the information that Palermo had been convicted of bigamy in Illinois in the 1950's and had later violated parole and left Illinois so that he was still a "fugitive from justice." The prosecution had been ordered, pursuant to a pre-trial defense motion, to make "every reasonable effort" to furnish the defense with the prior records of its witnesses. According to testimony at the new trial hearing by Detective Robert Patenaude of the State police, the investigating officer for the District Attorney on this case, normal practice was followed in obtaining the records of witnesses by requesting copies of their probation records from the State probation department. These records reveal with assurance only Massachusetts convictions. A copy of Palermo's record thus obtained was seasonably delivered to the defense. The prosecution did not seek records of out-of-State convictions. Such inquiry may be reasonable practice when known facts suggest that a witness has a record elsewhere, but we do not think it negligence amounting to constitutional error to omit to make broadcast inquiries in the absence of that kind of knowledge. Nor do we think the pre-trial order contemplated such an effort. Although Palermo did mention to the prosecution something about a bigamy "arrest" or "record," he said the incident had occurred in Massachusetts. Asked whether he had ever lived out-of-State, he appears to have replied in the negative. When the Massachusetts record revealed no conviction of bigamy, the Commonwealth could reasonably have dropped the matter on the assumption that only an arrest had occurred; extreme caution might have suggested a further inquiry, but omission to press the matter was not culpable neglect, much less intentional suppression of evidence. See Commonwealth v. Lewinski, 367 Mass. 889, 897-900 (1975). Cf. Giglio v. United States, 405 U.S. 150 (1972).

Nor is it remotely likely that the Illinois bigamy conviction, if put before the jury, would have carried weight with them. We may assume arguendo that the conviction would have been admissible for impeachment because Palermo can be said not to have finished serving his sentence, see G.L.c. 233, § 21; but we cannot suppose that commission of bigamy about twenty years in the past by a man now aged sixty-seven and living with a wife would much affect a jury. It would have added very little to other unavailing defense efforts to attack Palermo's credibility.

(b) The defense offered two new potential witnesses, William DeSimone and Timothy Mitchell, said to have been not previously available, who would testify that no shooting had occurred at the critical time and place. Affidavits from both men offered on the new trial motion recounted, in substantially similar words, that the affiant was present at the card game in the room above Dorothy's Cafe from 3 A.M. until 9 A.M. on the morning of May 6, and that Barry played cards from 3 A.M. to 7 A.M., when he went to the bar and stayed until he fell, knocking over a bar stool, at 7:30 A.M., whereupon he left the building. But on a motion for a new trial "[t]he weight and import of . . . affidavits . . . [are] for the trial judge's discretion"; even if undisputed, the affidavits need not be accepted as true; and the trial judge is "entitled to make use of his knowledge of what had taken place at the trial." Commonwealth v. DeChristoforo, 360 Mass. 531, 543 (1971). Here the judge could consider the fact that the affidavits were contradicted by testimony of several trial witnesses that Barry was not playing cards at 3 A.M. or thereabouts. Moreover, the judge heard live testimony on the motion from DeSimone (Mitchell being again unavailable) which he could assess as an indication of the value of all the new evidence proffered. DeSimone said that in April, 1973, he went to Dorothy's "a couple of times a week," and that he sometimes went upstairs to play cards (his affidavit stated that he "frequently visited the second floor"), but that since May 6, 1973, he had never visited the upstairs, and had visited the cafe below only "a couple of times." This testimony was offered to explain why DeSimone had not learned of the murder charge against Corradino until after the trial, more than nine months after the shooting allegedly took place. We think the judge could properly reject this part of the story as incredible, and accordingly disregard the rest of it, particularly as DeSimone was unable to select a picture of Barry out of a group of photographs although he claimed to know him well.

6. In discharge of our duty under G.L.c. 278, § 33E, we have reviewed all the evidence of which the substance has been outlined above. We find no reason to disturb the jury's verdict of murder in the second degree as to Corradino.

Judgments affirmed.