Police Your Planet is a science fiction novel by American author Lester del Ray, first published in 1956. 

Written under the pseudonym "Eric Van Lhin," this hard-boiled story of cheap grifters, Martian slums, and rampant crime featuring ex-cop Bruce Gordon.

This book presents a different take on the Mars settlement story - Mars is riddled with crime and political corruption that threatens the very existence of the colony. Bruce Gordon is exiled from Earth and dropped into the middle of the mess - as a newly assigned member of "Security" - with little information to go on. 

Bruce Gordon was an ex-fighter, ex-gambler, ex-cop, ex-reporter, and now he was an ex-patriot of Earth. Security shipped him to Mars with a knife, 100 credits, and a yellow card that meant no return.

He was also, he told himself, an ex-do-gooder. From then on he would take care of Number One! But in Marsport, nothing was that simple. Here the vices of Earth seemed tame and insipid.

When he bought a commission in the Marsport police force, he found that graft was not only a fine art, but the official Martian way of life. So he joined the system. And then he met Sheila, who was out for blood—his!

Lester del Rey (1915 - 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.

Del Rey was awarded the 1972 E. E. Smith Memorial Award for Imaginative Fiction (for the Skylark) by the New England Science Fiction Association and a special 1985 Balrog Award for his contributions to fantasy, voted by fans and organized by Locus Magazine. The Science Fiction Writers of America named him its 11th SFWA Grand Master in 1990.