The Sentencing Project is a Washington, D.C.–based research and advocacy centre working for decarceration in the United States and seeking to address racial disparities in the criminal justice system.

In 1981, Young became the director of a project of the National Legal Aid & Defender Association (NLADA) designed to establish defence-based sentencing advocacy programs.

In the late 1980s, The Sentencing Project became engaged in research and public education on a broad range of criminal justice policy issues.

The Sentencing Project works with other organisations and public officials to influence criminal justice policies at the federal, state, and local level.

University of Pittsburgh School of Law professor David Harris called Mauer "the go-to guy for any major media organization or any legislative body that wants the truth on what's been happening with our prisons and our jails ... His testimony to the Senate Judiciary Committee in October 2015 ... should be required reading for every public official in this country.