(concurring). The court today reaffirms its prior decision that a valid warrant authorizing the wiretap of a telephone line permits the installation of a cross frame unit trap to monitor that line. Ante at 694. See District Attorney for the Plymouth Dist. v. New England Tel. & Tel. Co., 379 Mass. 586, 591 (1980). Extending this rule, the court also holds that cross frame unit traps may be installed on separate telephone lines pursuant to a valid warrant authorizing multiple wiretaps. Ante at 694. This result is consistent with the court’s holding in District Attorney for the Plymouth Dist., supra. I concur, because I am bound by that decision.
I write separately to reiterate my concern for the privacy rights of callers whose telephone numbers might be caught up in the cross frame unit trap, where a wiretap alone may not have disclosed the identity of these callers. I adhere to my view that a finding of probable cause that telephone A is being used for criminal purposes does not necessarily support a finding of probable cause as to telephone B (and C, D, E, etc.). See id. at 598 (Liacos, J., dissenting). In my view, the court’s decision in District Attorney for the Plymouth Dist. did not address this issue adequately. While the record before us today does not present such a problem, there may arise a case where a cross frame unit trap yields evidence against a caller as to whose telephone there existed no probable cause to suspect criminal use. Should the government seek to prosecute such a caller, I believe that he or she would have standing to move for suppression of all evidence obtained pursuant to the unlawful surveillance.