District Judge Marvin J. Garbis was born in 1936 in Baltimore, Maryland. Judge Garbis obtained a B.E.S. from Johns Hopkins University in 1958, where he received the Westinghouse Scholarship, as well as the distinction of being members of Phi Alpha, Tau Beta Pi and Eta Kappa Nu. He attended Harvard Law School from 1958-61 and was honored with the Harvard Corp. Scholarship. Finally, Judge Garbis earned an LL.M. degree from Georgetown Law School in Washington, D. C. in 1962, and was honored with the E. Barrett Prettyman Fellowship.

In conjunction with the E. Barrett Prettyman Fellowship Program, Judge Garbis served from 1961-62 as a public defender in Washington, D.C. At this time, Judge Garbis joined the Tax Division of the U. S. Department of Justice in Washington, D. C. as a trial attorney, serving in this capacity from 1962-67. He entered practice in 1967, working first at the firm of Garbis and Schwait, followed by practice at Garbis, Marvel and Junghans, and finally at Melnicove, Kaufman, Weiner, Smouse and Garbis, all in Baltimore, Maryland. From 1988-89, Judge Garbis moved on to the firm of Johnson and Gibbs in Washington, D. C.

In July 1989, Judge Garbis received notification that he had been nominated by President Bush for appointment to a vacant seat on the United States District Court for the District of Maryland. This appointment was confirmed by the Senate on October 25, 1989, and finalized on December 8, 1989, when he was commissioned.  Judge Garbis took senior status on June 14, 2003.  He retired from the bench on June 26, 2018.

In addition to his legal and judicial duties, Judge Garbis authored seven books, including Cases and Materials on Tax Procedure and Tax Fraud, West Publishing Co., and Federal Tax Litigation, Warren Gorham and Lamont; as well as various articles on tax litigation and related matters.

Judge Garbis was admitted to the D.C. Bar in 1961 and the Maryland Bar in 1962. Memberships in professional organizations included the former president of the Maryland Institute for Continuing Professional Education of Lawyers (MICPEL); president of the Maryland Chapter of the Federal Bar Association; council member of the American Bar Association; and member of the MD Special Joint Committee on Gender Bias in the Courts. Judge Garbis was also a member of the adjunct faculty at the University of Baltimore, University of Maryland and the Georgetown Law Schools.