This is an appeal from denial of a motion to order an arrest record expunged. Irani, a graduate student with a security clearance due to federal employment, was arrested on February 19, 1970, for parading without a permit. On February 24, 1970, the District of Columbia determined not to prosecute “because of lack of evidence.” Irani then requested that the trial court order the records of the arrest be expunged.1 A hearing was held on the motion to expunge and by order dated March 27, 1970, the relief was denied.2
Factually, Irani established without contravention that he was arrested in connection with a civil disturbance at which he was innocently and unavoidably present, having just left a canceled class at a local university where the disturbance was in process. The reasons given for denying the motion were insufficiency of the facts to qualify as “unusual facts” under In re Alexander, D.C.App., 259 A.2d 592 (1969), and that there was no “ruling by the D.C. Court of Appeals that a dismissal * * * for lack of evidence is of itself a proper ground to order expungement of an arrest *851record. * * * ” We reverse and remand for an exercise of judgment by the trial court as to the form of relief which it may deem appropriate.
The argument made by the District of Columbia for the first time on appeal, that the trial court lacked jurisdiction to consider the motion, is not well taken. It urges that since no case in the form of a prosecution was brought before the court there is no case in which to exercise this special ancillary power.
Whether there is formal subject matter jurisdiction in the nature of a docketed case over a subsequent prosecution need not be the exclusive basis for an order limiting use of an arrest record. In the District of Columbia, jurisdiction of the trial court over the person arrested is provided by D.C.Code 1967, § 23-610. That provision allows police officers to be designated to act as clerk of the court to accept bail or collateral when the court is not open and the clerk accessible. In fact, Irani posted collateral with such court official at the police station after he was charged on police records by the arresting officer. See also Fed.R.Crim.P. 5. What is apparent is that jurisdiction over the subject matter of the arrest is conferred by this provision. Therefore, consistent with the holding in Morrow v. District of Columbia, 135 U.S.App.D.C. 160, 417 F.2d 728 (1969), there is a case relating to the arrest before the court out of which it might act on a motion to limit use of the arrest record. It is recognized that Morrow held that the trial court “does have the power to issue an order regarding the arrest record in a criminal case which has been before the court.”3 We do not read that holding as dictating the outer limit of ancillary jurisdiction to treat the question of limiting use of arrest records, thus leaving ¡persons like Irani to their remedy in the United States District Court. E.g., Menard v. Mitchell, 430 F.2d 486 (D.C.Cir., 1970).
We now reach the question whether it was legally correct to deny the relief sought. It is noted that the trial court denied the requested relief because of the absence of an appellate holding that a decision not to prosecute “for lack of evidence” is sufficient reason “to qualify as ‘unusual facts’ ” within our holding in In re Alexander, supra. But more appears on this record, however, than a mere determination by the prosecution that it lacked enough evidence for conviction. Irani did just as we contemplated in In re Alexander, supra. He affirmatively established that he was innocently present for legitimate reasons and that his arrest was a mistake. We conclude that such circumstances reveal a “rare case presenting such unusual facts as to justify” some relief. In re Alexander, supra, 259 A.2d at 593. Accordingly, we hold that where one arrested for an offense successfully makes an affirmative demonstration negating factual guilt, it is error to deny relief outright.
Reversed and remanded.
. Morrow v. District of Columbia, 135 U.S.App.D.C. 160, 417 F.2d 728 (1969).
. The motion embodied a request to order destruction of all photographs and fingerprint records relating to Irani’s arrest. Also requested was an order enjoining official or private dissemination of the arrest records, and compelling disclosure whether and to whom such dissemination had already been made.
. Morrow v. District of Columbia, supra note 1, 135 U.S.App.D.C. at 173, 417 F.2d at 741.