Police Your Planet

Hint: You can preview this book by clicking on "Preview" which is located under the cover of this book. About the author: Lester del Rey (June 2, 1915 – May 10, 1993) was an American science fiction author and editor. He was the author of many books in the juvenile Winston Science Fiction series, and the editor at Del Rey Books, the fantasy and science fiction imprint of Ballantine Books, along with his fourth wife Judy-Lynn del Rey.Del Rey often told people his real name was Ramon Felipe Alvarez-del Rey (and sometimes even Ramon Felipe San Juan Mario Silvio Enrico Smith Heartcourt-Brace Sierra y Alvarez del Rey y de los Uerdes). He also claimed that his family was killed in a car accident in 1935. Excerpt from: https://en.wikipedia.org/wiki/Lester_del_Rey