Massachusetts General Laws Part IV. Crimes, Punishments and Proceedings in Criminal Cases (Ch. 263-280) Ch. 276, § 20P

Nothing in sections eleven to twenty O, inclusive, shall be deemed to constitute a waiver by this commonwealth of its right, power or privilege to try any person demanded of it for a crime committed herein, or of its right, power or privilege to regain custody of such a person by interstate rendition proceedings or otherwise for the purpose of trial, sentence or punishment for any crime committed herein, nor shall any proceeding under said sections which result in, or fail to result in, interstate rendition be deemed a waiver by this commonwealth of any of its rights, privileges or jurisdiction in any way whatsoever.