In the mid-1950s, he legally changed his surname to match his clown persona, as there was already a Broadway actor named Paul Brown.

In 1946, he joined the United States Navy and served for two years before returning home and graduating from West Virginia University in 1952.

He created and was one of the head writers on The Electric Company, produced by the Children's Television Workshop for PBS in the United States.

[2] Some of the characters Dooley created for The Electric Company included Easy Reader (Morgan Freeman) and Fargo North, Decoder (Skip Hinnant), as well as the soap opera spoof Love of Chair.

[2] Dooley formed a company with Andrew Duncan and Lynne Lipton called All Over Creation to create commercials for radio and television.

[6] Dooley has also appeared as a variety of recurrent characters on numerous television shows, including ER, My So-Called Life, Dream On, Grace Under Fire, thirtysomething, Curb Your Enthusiasm, ALF (playing Whizzer Deaver), Chicago Hope, and Star Trek: Deep Space Nine where he played the recurring role of Enabran Tain.

He guest starred in other primetime shows like Bewitched, The Wonder Years, Sabrina, the Teenage Witch, Hot in Cleveland, and Desperate Housewives.

[8] Dooley starred in the short-lived comedy about a couple living in an Arizona retirement community, Coming of Age, opposite veteran actors Phyllis Newman, Glynis Johns and Alan Young.

[9] In 2014, he appeared in an episode of the NBC series Parenthood as Rocky, a fellow vet and retiree to Craig T. Nelson's Zeek Braverman.

[10] In 2017, he appeared in the episode "22 Steps" of the ABC series The Good Doctor as Glenn, a 72-year-old man with a failing heart who breaks his pacemaker because he wants to die due to the constant pain he is suffering.