He attended the University of Washington, where, as a freshman, he became the editorial cartoonist of the student newspaper The Daily.
Horsey's first job was as a reporter for the Bellevue Journal-American, but in 1979 he was hired to be the editorial cartoonist of the Post-Intelligencer.
At the end of 2011, he left the Post-Intelligencer and went to work for the Los Angeles Times,[2] where he remained until January 2018.
In 2014, he was again a finalist for the Pulitzer Prize and also received the Robert F. Kennedy Journalism Award for his cartoons related to social justice issues.
In November 2017, Horsey wrote an entry for his thrice-weekly column, Top of the Ticket, in the Los Angeles Times titled "Sarah Huckabee Sanders is the right mouthpiece for a truth-twisting president" and was criticized shortly thereafter for his disparaging remarks about the appearance of Donald Trump's press secretary, Sarah Huckabee Sanders.