This is an appeal under G. L. c. 278, Sections 33A-33G, from convictions of rape and assault and battery by means of a dangerous weapon. The defendant, a black man, argues a single assignment of error, the denial of his motion "to allow more than one black to sit in the defendant's dock to insure proper identification of defendant in court," a request in substance for an in-court lineup for identification purposes at trial. There is no constitutional requirement that in-court identification of a defendant be conducted as a lineup. Commonwealth v. Wheeler, ante, 387, 391 (1975). Whether to accede to the defendant's request for an in-court lineup rested within the sound discretion of the judge. See Commonwealth v. Bumpus, 362 Mass. 672 , 680 (1972), judgment vacated on other grounds, 411 U.S. 945 (1973), affd. on reh., 365 Mass. 66 (1974). Obviously, an element of suggestion existed in the relative isolation of the defendant in the dock. It has been held, nonetheless, that "counsel [for the defendant] has the responsibility, by way of cross-examination, to bring to the attention of the trier of facts any circumstances which tend to cast doubt upon a witness's identification testimony." Commonwealth v. Jones, 362 Mass. 497 , 500-501 (1972). Absent a showing of an abuse of discretion which prejudices the defendant's opportunity for a fair trial, the judge's ruling is not to be disturbed. There is no such showing here. Cases upon which the defendant places reliance dealt with assertions that in-court identifications were tainted by prior impermissible out-of-court confrontations between the witness and the defendant. Here there had been no such confrontation, suggestive or otherwise, and the victim was permitted to identify the defendant as her assailant at the trial held thirteen months after the assault. Contrary to the defendant's assertion, the victim not only had ample opportunities prior to, during and immediately following the assault to observe her assailant but also, as the record shows, to receive "a firm contemporaneous impression" of him not likely to have been influenced by subsequent events. Commonwealth v. Ross, 361 Mass. 665 , 672 (1972), judgment vacated on other grounds, 410 U.S. 901 (1973), affd. on reh., 363 Mass. 665 (1973).
The defendant was found guilty after a jury-waived trial in the Superior Court on separate indictments which charged him with assault and battery by means of a dangerous weapon and rape, respectively. The cases were tried pursuant to G. L. c. 278, Sections 33A-33G. The appeal presents only the question whether the trial judge's viewing of the complainant's chest and facial wounds during the course of the trial was an abuse of discretion because the scars were allegedly irrelevant, gruesome, and inflammatory. Errors assigned but not argued are deemed waived. There was evidence that the defendant and the complainant had known each other prior to the incident in question, that the defendant was visiting the complainant's apartment, that there was a disagreement over the defendant's use of her telephone for a long distance call, and that the defendant then beat and raped the complainant
and thereafter slashed her with a knife both on her face and on one breast. The judge viewed the wounds in his role as the finder of fact. The defendant stipulated that there were marks indicating injury on the complainant's face and chest but disputed the manner in which she alleged the lacerations occurred. After having ascertained from the prosecution that it would ask the factfinder to infer from the scars the method by which the wounds were inflicted (Cf. Horowitz v. Bokron, 337 Mass. 739 , 742 ), the judge determined that if a jury had been present, he would have permitted them to view her injuries. See generally, Commonwealth v. Farrell, 322 Mass. 606 , 609-611, 616-620 (1948). The wounds were relevant to ascertaining whether the defendant actually used the knife introduced in evidence to slash her. See Commonwealth v. Chalifoux, 362 Mass. 811 , 817 (1973). The trial judge, sitting without a jury, is presumed, absent contrary indication, to have correctly instructed himself as to the manner in which evidence was to be considered in his role as factfinder. Cummings v. National Shawmut Bank of Boston, 284 Mass. 563 , 568 (1933). Cambridge v. West Springfield, 303 Mass. 63 , 69 (1939). The admission of demonstrative evidence is a matter of discretion for the trial judge. Blanchard v. Holyoke St. Ry. 186 Mass. 582 , 583 (1904). Tuttle v. McGeeney, 344 Mass. 200 , 205 (1962). Commonwealth v. D'Agostino, 344 Mass. 276 , 279 (1962), cert. den. 371 U.S. 852 (1962). Commonwealth v. Stirling, 351 Mass. 68 , 72 (1966). Commonwealth v. Torres, 367 Mass. 737 , 742 (1975). We see no reason to disturb his determination that the probative value of viewing the scars outweighed any potential prejudicial effect.