Then they hit traffic, and respect for the dead falls by the wayside.
Drivers cut into the procession, they block its passage, they lean on their horns.
They ignore the "Funeral" signs on each car. They pay no mind to the blink of emergency lights or shine of headlights. They show no interest in making way for the passing of the dead.
"People do not give respect to the funeral as they did years back," Wilson said. "Everybody's busier, and there are more cars. But people should still be showing respect."
Even as the pace of daily life has quickened with each passing decade, Wilson said, the somber passage of a funeral caused people to slow down and, he liked to think, perhaps ponder their own mortality. Now, he said, everyone "seems in a hurry to get nowhere."
Although undertakers attest that traditional respect has taken a beating in the hurly-burly, go-go atmosphere on the region's congested roads, the phenomenon is far from unique to the Washington area.
At least two people have been killed and 23 injured nationwide this year in funeral procession accidents, according to research by AAA that will be released Wednesday.
While the worst of them was in congested New York, where a minivan cut off a funeral limousine in a crash that sent 16 people to the hospital, others were in less-urban settings. Five of the six people killed in 2011 were police officers escorting processions.
"This caliber of macabre disrespect was unthinkable a generation ago," said John B. Townsend II of AAA.
Wilson said a van once drove up on the sidewalk to get around a procession he was leading through the gates of a cemetery, clipping off the bumper of his hearse. On another day, an impatient driver darted between a police escort and the hearse as a cortege passed through the intersection of Bladensburg and New York avenues, racing off toward Maryland - with police in pursuit.
Wilson works at R.N. Horton's Funeral Home in Northwest Washington, but he delivers the deceased and those who grieve for them to cemeteries across the region.
"Regardless of what cemetery you're going to, you have that busy traffic, and people don't want to stop," he said. "You may have some cars stopped, and other cars run around them."
Things were very different a quarter-century ago, when Archer Harmon began his career in the funeral business in Fairfax County. In those days, cars would pull to the side of the road to let a funeral procession pass. Now, he said, many drivers simply won't wait.
"It's clear what is going on, and they still cut between the cars," said Harmon, general manager of Fairfax Memorial Funeral Home. "We have cellphones in one hand, Starbucks in the other and what is in front of you doesn't matter at that point. They just don't care, in this society we live in now."
Harmon also wondered whether the region's international diversity might contribute to confusion over funeral procession tradition.
"It may be cultural," he said. "There are some people here who may not know what a funeral procession is."
But while the particulars vary from one culture to the next, showing respect for the dead and the mourners has been universally embraced. And that respect is what funeral directors see waning.
"You can sit at a traffic light for a couple of minutes to show respect so that a funeral can go through," Wilson said. "But, no, you've got to blow your horn, you've got to run between a procession. But when the shoe's on your feet, you want everybody to stop."
Americans spend about $12 billion a year on funerals.
The District and both adjoining states have laws that give funeral processions certain rights of way, including passing through red lights in most situations.
Getting police to escort a funeral motorcade is easier in some Washington jurisdictions than others. Short-handed departments can't comply with all requests, and some charge funeral directors for the service.
Wilson said it isn't so bad everywhere as it is around Washington.
"If you go to the South, they show respect," he said. "In the eastern part of North Carolina, the people pull to the side of the road on both sides, regardless of what race is being buried, black or white. They still show some respect."