Spencer Phipps Boyer is an American foreign policy, national security, and international law and relations expert who served as deputy assistant secretary of defense for Europe and NATO in the Biden administration.

[5] After returning to the United States, Boyer joined Georgetown University as the executive director of the Constitution Project at the McCourt School of Public Policy.

[7] In January 2009, Boyer was named as deputy assistant secretary of state for European and Eurasian affairs with responsibility for Western Europe, where served for two years.

He then joined the Center for Transatlantic Relations at the Paul H. Nitze School of Advanced International Studies at Johns Hopkins University a visiting scholar and senior fellow.

After leaving government, Boyer was then named as the director of the Washington, D.C. office of the Brennan Center for Justice.