OPINION OF THE COURT
Memorandum.
The order of the Appellate Division should be affirmed.
The sole issue raised for our consideration is whether the absence in the record of proof that the District Attorney *775complied with the direction of the court issuing the warrant to file interim progress reports during the pendency of a wiretap necessitates suppression of the tapes obtained pursuant to that warrant.
The wiretap was authorized by an eavesdropping warrant issued on March 14, 1974 which required that "reports * * * be made to this Court by the District Attorney of Queens County, or his agent, fifteen (15) days after the installation of the electronic equipment stating the substance of the conversations seized and the progress of the investigation”. The record does not disclose compliance with this direction. On April 16, 1974, based on an application which reported the results of the ¡entire month’s interceptions, the eavesdropping warrant was extended for a second 30-day period.
The statute (CPLR 700.50, subd 1) does not itself require the filing of interim reports; rather it authorizes the issuing court to require such reports, apparently to facilitate judicial supervision of the wiretap. Whatever may be the range of judicial sanctions for failure to comply with such a directive, failure to do so, at least in the absence of any demonstration of substantial prejudice to the defendant, does not require suppression of the tapes or of derivative evidence. In this instance, defendant claims no prejudice other than pointing to the speculative possibility that had the required report been made the tap might have been terminated. Even this theoretical possibility may be disregarded in this instance, however, in view of the subsequent issuance of the extension order based on the delayed but more comprehensive report of the results of the original tap. In any event we observe that, while an interim report if filed as directed might have precipitated a termination of the wiretap by the issuing Justice, the failure to file such a report in no way exposed the intercepts themselves to risk that their fidelity might be compromised.