Quash means to nullify, void or declare invalid. The procedure is used in both criminal and civil cases when there is an irregularity or defect in procedures. A motion to quash is often made in regard to the issuance of a subpoena. There are various reasons which may be given for why a subpoena should be quashed. One common reason advanced is that the information sought is confidential or privileged against disclosure. Another reason that may be given, among others, is that compliance with the subpoena would be unreasonable, oppressive, or unduly burdensome.
The following is an example of a statute dealing with a motion to quash:
"Sec. 70.27 Right to intervene; right to institute a proceeding to quash.
(a) Notified person. Under 26 U.S.C. 7609(a), the Bureau must give a notice of summons to any person, other than the person summoned, whois identified in the description of the books and records contained in the summons in order that such person may contest the right of the Bureau to examine the summoned records by instituting a proceeding to quash the summons. Thus, if the Bureau issues a summons to a bank requesting checking account records of more than one person all of whom are identified in the description of the records contained in the summons, then all such persons are notified persons entitled to notice under 26 U.S.C. 7609(a). Therefore, if the Bureau requests the records of a joint bank account of A and B, both of whom are named in the summons, then both A and B are notified persons entitled to notice under 26 U.S.C. 7609(a)."