As she stepped past her mother’s coffin and around an altar rail where her mother took Communion in running shoes and shorts, the narrow road where Trish Cunningham died violently seemed very distant from the church sanctuary that had now fallen silent.

“This summer, my Aunt Colleen nailed Trish in five words: ‘Your mom is a force,’ ” said Morgan Cunningham, 20, as she began a eulogy that left people laughing through tears. “The force is my mother and my best friend. I am extremely proud and thankful to say that.”

On Saturday, 33 days after she spoke at her mother’s funeral, Morgan Cunningham pedaled her bicycle down to a place in the road still marked with the blue paint that police use for bad accidents. Her mother was killed there, just south of Annapolis, on Aug. 21 by a driver who tried to pass her as she rode her bike up a hill on an 18-foot-wide road that has no shoulders.

“I will do anything to get my mom’s story out there and prevent this from happening again,” Morgan said.

As if to drive home that point, she spent the morning leading hundreds of cyclists — among them her father, Jerry, and sister, Avery — to erect a symbolic bicycle, painted pure white and known as a “ghost bike.”

Already, the death of Trish Cunningham, a popular youth and high school coach, avid member of her church and well-known runner, has taken on a greater meaning. It has fueled discussion on the presence of cyclists on increasingly congested highways and on the laws that govern behavior of riders and drivers. It also has launched a torrent of e-mails to a county prosecutor, urging that the driver, Whitney Anne Decesaris, 37, of Huntingtown face charges. The prosecutor is expected to make a decision within days, and he said the possibilities range from involuntary manslaughter, to violation of the state law requiring drivers to stay at least three feet from cyclists, to a traffic citation, to a determination that the driver was not at fault.

‘The driver couldn’t wait?’

The day 50-year-old Trish Cunningham died, she had finished up coaching one of the first cross-country practices of the season, one that had her more fired up than usual because her daughter, Avery, was a new freshman member of the Annapolis High team.

She hopped on her bike and headed down Riva Road, a busy boulevard that winds south from the city before turning into a less traveled two-lane road.

As she neared the crest of a hill, a driver who had come upon her from behind attempted to pass her, although there was no way of telling whether oncoming traffic was about to appear from the opposite side of the hill. Police were told that there was a car coming the other way, and that the driver swerved back to the right and slammed into Cunningham.

Jerry Cunningham started to worry that evening when darkness fell and his wife had not returned from her ride. His daughter used a cellphone app to locate her mom. She’s just down the road, she said. Jerry figured she must have had a flat tire, so he set out to fetch her. As he neared her location, he found the road barricaded by police cars with lights flashing. They stopped him from approaching the crash. After a while, four officers came out down the road to talk with him.

A preliminary police report said “driver error” was the apparent cause.

On Saturday, Jerry Cunningham spoke to the assembled riders before they set out.

“At her speed, Trish could get up that hill in about 15 seconds,” he said. “Fifteen seconds? The driver couldn’t wait 15 seconds?”

Chasing down drivers

The first known crash between two vehicles in the United States occurred in 1896, when a New York driver collided with a bicyclist.

Both driver and cyclist survived that one. But since record-keeping began in 1932, about 55,000 cyclists have died in traffic crashes. Nationally, a cyclist is killed every 12.6 hours on average; 48,000 people were injured in traffic accidents in 2011.

Some fatal bike crashes make the news. Joy Covey, who was a former chief financial officer of, was killed by a driver who turned into her path as she pedaled down a rural California roadway 10 days ago. A pair of middle-aged women died in New Hampshire last weekend when a driver crossed the center line and plowed through a group of cyclists. And a budding pop musician was sentenced to 12 years in prison this month for killing a cyclist in Miami.

According to the most recent data available, 51 cyclists have been killed in the Washington region in the past five years.

Although bike crashes are on the increase, few of them receive as much attention as the one that killed Trish Cunningham.

When Maryland legislators approved a law in 2010 that said drivers must stay at least three feet away when passing a bicyclist, the cynics said it was a nice gesture, but no one expected police officers with yardsticks to go about enforcing it.

In the aftermath of Cunningham’s death, her friends and family are mounting educational efforts to encourage drivers to abide by the law. That message was a focus of Saturday’s rally and memorial ride.

Cycling advocates in Maryland have suggested that the state replace those “Share the road” signs with signs that remind drivers, “Three feet, it’s the law.”

Bikers elsewhere are using other tactics to prevent deaths.

In Delaware, cycling groups have asked the state to do away with the long-term “Share the Road” campaign, saying it confuses people.

“Many motorists believe that ‘sharing’ means giving up part of something they believe is rightfully theirs, while cyclists tend to think of sharing as referring to a commonly owned asset that belongs to them just as much as it does to motorists,” the Bike Delaware group said in a letter to the state’s chief highway engineer.

In Texas, police in Austin found a way to enforce their three-foot law. They sent a pair of plainclothes officers out on bicycles with a patrol car to chase down and ticket drivers who passed too close.

They figured a $167 ticket would better get people’s attention than a warning sign.

A shattered cellphone

On Saturday, Morgan Cunningham addressed the crowd of cyclists gathered in the parking lot of the high school from which she graduated and at which her mother coached.

She spoke of the policeman who arrived in her driveway after the crash to deliver her mother’s belongings collected at the crash site. She said the physical impact of the crash on her mother and the full emotional weight of the loss bore down on her when she was handed her mother’s cellphone. It had shattered inside its hard-shell case.

Morgan hid it in a dresser drawer.

“I don’t like to open that drawer anymore,” she said.

A few weeks earlier, on Labor Day, Morgan had joined dozens of cyclists who fanned out at two Anne Arundel County intersections, waving signs to raise awareness about the three-foot law. It wasn’t a demonstration or a protest, they said. It was a plea to drivers: There’s room, and a proper place, on the road for everyone.

“Three feet, it’s the law,” read one sign.

“Please drive gently. My kids thank you,” read another.

Morgan Cunningham’s sign simply said, “Trish.”