Thе defendant was convicted of robbery and mayhem in a jury waived trial in the Superior Court in *459 1973. 1 A motion for a new trial was denied by the trial judge without a hearing in 1978. The defendant was allowed to file a late noticе of appeal under G.L. c. 278, §§ 33A-33H, from both his convictions and the denial of his motion for a new trial, and the two appeals were consolidated.
The facts of the case are related in
Commonwealth
v.
Michel,
The defendant was indicted for robbery and mayhem of Cole along with three codefendants. January 23, 1973, at the commencement of trial, all four defendants filed written waivers of their right to trial by jury. 3 According to affidavits filed in support of the defendant’s motion for a new trial, all four defense, counsel recommended this strategy to their clients in the belief that the evidence was insufficient as a mаtter of law, and that a trial judge would be more inclined to grant a motion for a directed verdict when no jury had been impanelled and sworn.
During the trial, Cole did not identify the defendant as one of his assailants. There was testimony, however, that the day after the incident Cole picked three pictures out of an array of photographs; one of the photographs was that of the defendant. 4 The only testimony at trial involving the *460 defendаnt in Cole’s assault came from Walter D. Coyne, III. Coyne was originally indicted for these offenses, but was acquitted by the judge after he objected to the Commonwealth’s motion to enter a nolle prosequi on the charges against him during trial. Coyne’s testimony at trial was consistent with a statement he had given to the police within two weeks of the incident. Coyne inculpated his codefendants and exculpated himself.
On appeal Dietrich argues that his waiver of jury trial was not knowing and intelligent since it was based on a mistaken evaluation of the strength of the Commonwealth’s case against him because of Coynе’s appearance at trial as a prosecution witness. He further claims reversible error in the trial judge’s failure to declare a mistrial on his own motion when Coyne began to testify for the Commonwеalth. Finally, he claims that the identification procedures involved in this case were so impermissibly suggestive that their subsequent use at trial was a due process violation. We find no merit in any of these contentions and affirm the judgments.
Waiver of jury trial.
Since the defendant did not challenge the validity of his jury waiver until he filed a motion for new trial, we review the record to see whether there is a “substantial risk of a miscarriage of justicе.”
Commonwealth
v.
Freeman,
The right to a jury trial is a fundamental right guaranteed to a criminal defendant in order to preserve a fair trial. A defendant may waive that right only if he does so knowingly and intelligently.
Schneckloth
v.
Bustamonte,
The defendant does not claim that he misunderstood the scope and impact of this precious constitutional right. See
Ciummei
v.
Commonwealth, 378
Mass. 504, 508-509
*461
(1979);
United States
v.
Conforte,
Dietrich argues that “it [was] perfectly clear to the Commonwealth prior to trial that it [would] be necessary to ‘make a deal’ with one of the defеndants in order to secure convictions.” If it was perfectly clear to the Commonwealth, however, it was equally clear to the defendant. The defendant knew that shortly after the incident Coyne had given the police a statement inculpating all three of his codefendants and exculpating himself. Therefore, the probability that Coyne might strike a deal and decide to testify for the Commonwealth was an obvious consideration in deciding whether to waive a jury.
The decision whether or not to waive the right to trial by jury is primarily “a decision regarding trial strategy.”
Ciummei
v.
Commonwealth, supra
at 508 n.7. “In the end, the defendant must make an over-all estimate as to where he will fare better, before a judge or before a jury. If he goes to trial, he will presumably prefer to go to trial in the
*462
forum where he thinks his chances will be best.” H. Kalven & H. Zeisel, The American Jury, 28 (1966). The defendant will not be relieved of the consequences of his tactical decision where the circumstances which are said to warrant relief were clearly foreseeable at the time of the waiver. See
United States
v.
Conforte,
The defendant also asserts that he relied on advice from Anthony DiFruscia, attorney for codefendant Michel, in deciding whether to waive his right to trial by jury. Since Michel’s attorney had conflicting allegiances, see Commonwealth v. Michel, ante 447 (1980), Diеtrich claims his waiver was somehow thereby tainted. The short answer is that the defendant had the benefit of independent counsel in making his tactical decision and cannot prosper by bootstrapрing Michel’s claim. We give considerable deference to tactical determinations made with the advice of independent counsel. See Commonwealth v. Michel, supra at 454 n.9.
Mistrial. The defendant did not move for a mistrial at any pоint in the proceedings below, nor did he ever request permission to withdraw his waiver of a jury trial. In this court, he argues that the judge had an obligation to declare a mistrial on his own motion. In the absence of circumstances which would justify voiding the defendant’s waiver of jury trial, we do not think the judge had an obligation, or indeed the right, to declare a mistrial when Coyne began to testify for the Commonwealth.
The defendant asserts that the judge’s conduct in acquitting Coyne rather than letting the Commonwealth enter a nolie prosequi amounted to an exercise of the prosecutorial function which seriously impinged on the neсessary impartiality of the trial judge. This argument is without merit. The defendant’s argument fails to consider fully the fact that jeopardy attaches when the defendant is put on trial.
Commonwealth
v.
Clemmons,
Finally, as to the questions asked by the judge, “[i]t would add little to our jurisprudence to discuss in detail the defendant’s attacks on the judge’s questioning of witnеsses,”
Commonwealth
v.
Hanscomb,
Identification.
Evidence of Cole’s out-of-court identification of the defendant’s photograрh was admitted over his objection and exception at trial. See note 4,
supra.
The defendant now argues that the photographic identification procedure employed by the Commonwealth “wаs so imper-missibly suggestive as to give rise to a very substantial likelihood of irreparable misidentification.”
Simmons
v.
United States,
The defendant’s objections focus on the size of the array, whether Cole was physically and mentally competent to make an identification, and whether the officer’s comments were overly suggestive. In evaluating whether a given identification procedure is unnecessarily suggestive, we considеr “the totality of the circumstances surrounding it.”
Commonwealth
v.
Botelho,
*464
An array of ten photographs is not as a matter of constitutional law too small. Further, the fact that three of the ten photographs were those of thе three defendants (Michel and the two Dietrichs) does not, without more, render the array an unfair sample. See
Commonwealth
v.
Cincotta,
Judgments affirmed.
Notes
The defendant was sentenced to fifteen to fifty years at the Massachusetts Correctional Institution at Walpole on the robbery conviction, with a concurrent term of fifteen to twenty years for mayhem.
See also Commonwealth v. Michel, ante 447 (1980).
See G. L. c. 263, § 6; Mass. R. Grim. P. 19 (a),
It was unclear whether Cole identified photographs of the Dietrich brothers and Michel as his assailants or simply as his companions on the day of the beating. The Commonwealth acknowledges that this testimony is ambiguous.
In
People
v.
Redwine,