He was the founder and editor-in-chief of the Washington Monthly magazine and the author of We Do Our Part: Toward A Fairer and More Equal America (Random House, 2017).

His practice included libel, criminal defense, corporate and labor law, as well as representing plaintiffs and defendants in civil trials.

After returning to serve in the 1962 legislative session, he was named the Peace Corps' director of evaluation, a position that required him to report on the performance of the agency's programs overseas and on how they could be improved.

[citation needed] Its articles included "The White House Staff vs. the Cabinet," "What Happens to a Senator's Day," and "The Data Game."

Among them were Taylor Branch, Suzannah Lessard, James Fallows, Walter Shapiro, Michael Kinsley, David Ignatius, Nicholas Lemann, Gregg Easterbrook, Mickey Kaus, Joe Nocera, Jonathan Alter, Timothy Noah, Steve Waldman, Matt Cooper, Jason DeParle, James Bennet, Katherine Boo, and Jon Meacham.

[4] Peters served as editor of the Washington Monthly until he retired in 2001, but continued to write a regular column Tilting at Windmills for the magazine until 2014.

[citation needed] In 1957, Peters married Elizabeth Hubbell, a former ballet dancer who had attended Vassar College.

[2] After several years of poor health due to heart failure, Peters died at his home in Washington, D.C. on November 23, 2023, at the age of 96.