For those who didn't like the message or the tactics, Phelps and his family had only disdain. "They need to drink a frosty mug of shut-the-hell-up and avert their eyes," his daughter, Shirley Phelps-Roper, once told a group of Kansas lawmakers.
The activities of Phelps' church, unaffiliated with any larger denomination, inspired a federal law and laws in more than 40 states limiting protests and picketing at funerals. He and a daughter were even barred from entering Britain for inciting hatred.
But in a major free-speech ruling in 2011, the U.S. Supreme Court held that the church and its members were protected by the U.S. Constitution's First Amendment and could not be sued for monetary damages for inflicting pain on grieving families.
Yet despite that legal victory, some gay rights advocates believe all the attention Phelps generated served to advance their cause.
Sue Hyde, a staff member at the National Gay and Lesbian Task Force, said plenty of churches and ministers preach a message that attacks gay people. But Phelps and his family had "taken this out on the streets," forcing people to confront their own views and rousing a protective instinct in parents and friends of gays and lesbians.
"It's actually a wonderful recruiting tool for a pro-equality, pro-social acceptance movement," she said. "To the Phelps family, that is not particularly important or relevant. They are not there to save us. They are there to advise us that we are doomed."
Once seen as the church's unchallengeable patriarch, Phelps' public visibility waned as he grew older and less active in the church's pickets, with daughters Shirley Phelps-Roper and Margie Phelps — an attorney who argued the church's case before the U.S. Supreme Court — most often speaking for Westboro. In the fall of 2013, even they were replaced by a church member not related to Phelps by blood as Westboro's chief spokesman.