ST. PETERSBURG – Ralph Parker had shown signs of dementia before, but his condition worsened dramatically over the past week. Argumentative one minute, calm the next.

Alarmed, Parker’s son left Idaho on Wednesday to get his 93-year-old father in a safe place, police said.

Before he could get here, his dad backed his gold Chevrolet Malibu out of the driveway and went for a drive.

It ended horribly. Parker hit a man crossing 34th Street S, severing the man’s right leg, then drove 3 miles with the body stuck in the windshield.

When police asked Parker what happened, he said the body seemed to drop from the sky.

Parker thought it was December and that he was headed home to Pinellas Park, not south toward the Sunshine Skyway bridge, police said.

The case is an extreme example of a complicated and enduring issue in Florida and everywhere: When is someone too old to drive? Experts say there is no reliable test or quick answer.

Unless something changes, they say, the problem will only get worse.

Julia Zumpf was driving south on 34th Street about 8:30 p.m. Wednesday when she saw the gold Malibu unsteady in the road.

Drunken driver, she thought.

Then Zumpf, 44, saw a pedestrian step off the center median and head across the three-lane road.

“He didn’t even walk straight across, he walked at a 45-degree angle toward the cars,” Zumpf. “It reminded me of some cocky kid who walks in front of you.”

The driver of the Malibu slammed on his brakes, Zumpf said.

She thought the driver missed him but suddenly she heard a crash and saw a leg flying in front of her blue Buick LeSabre.

“It went at least one story in the air,” she said.

His shoe then popped off before the limb came to a rest on a strip of grass west of the street, in front of Howard Johnson’s.

The driver kept going, as if not realizing what happened, Zumpf said. She drove several blocks, trying to locate the body, thinking it rolled off the car, and called 911.

“I thought it was just a hit-and-run,” she said.

The body was still on the Malibu. The head and shoulders were punched through the windshield, the torso slung backward over the hood.

Three miles later, the car approached the Sunshine Skyway toll bridge. As Parker decelerated, the body slumped entirely inside, the man’s face pushed up against the dash.

The macabre scene looked like a Halloween prank to the toll taker. Then she saw the blood.

Police had not released the name of the victim as of late Thursday.

He was 52 and lived at the Crystal Inn across the street from the scene of the accident. The man, often seen begging for money on 54th Avenue S, was going to McDonald’s for something to eat, police said.

Residents at the hotel said his first name was Rudy. They said he was a hard drinker, but a decent man with long ties to St. Petersburg.

The fractured windshield obscuring his view, and blood streaming down the console, Parker told police he did not realize what happened until he reached the tollbooth.

Even then, he thought a body dropped from above, perhaps a pedestrian overpass, said St. Petersburg police Officer Michael Jockers.

“He may have somewhere in his mind have realized it was a crash, but immediately forgot about it,” Jockers said.

Bruce Bartlett, chief assistant in the Pinellas-Pasco State Attorney’s Office, said it was unlikely the state would file charges.

No final decision will be made until the police investigation is completed.

To charge Parker with leaving the scene of a crash, prosecutors would have to prove he knew or should have known there was an accident. Additionally, he would have to be mentally competent to stand trial. Parker did not appear to know what happened, where he was or why he was there when he spoke with police officers, Bartlett said.

Jockers took Parker’s driver’s license. Short of having the state take it away forever, Parker will have to take a test to show he is still competent behind the wheel.

Parker hasn’t been cited for any serious driving incidents during the past seven years, according to state records. His history is clean except for an expired tag. He last renewed his license in 2003, at the age of 91. It was set to expire in 2010.

A spokesman for the state Department of Highway Safety and Motor Vehicles said the agency would conduct its own inquiry into whether Parker should have had a license.

“We will investigate this vigorously to see how this could have been prevented, if at all,” said spokesman Frank Penela.

In recent years, experts have sounded warnings about the risks of elderly drivers and the need for more comprehensive screenings. A state report released last year said Florida was facing a “critical situation with its aging population: the mature at-risk driver.”

The issue has gotten more attention because older drivers are living longer, buoyed by better medical treatment.

Last year, nearly 270,000 people age 85 or older were licensed to drive in Florida. Of those, at least 20 percent are considered “dementia drivers,” with a mild to moderate condition, according to a 2004 state report.

Yet Florida, like many states, has no comprehensive system for evaluating whether older residents should be on the road.

The only age-related requirement is that seniors age 80 or older must pass a vision test when renewing their license, generally every six years.

That went into effect Jan. 1, 2004, two months after Parker last renewed his license.

But vision tests do not reveal other factors that affect driving, such as Alzheimer’s disease, side effects from medication and chronic health problems.

While Florida and other states say they would welcome more comprehensive screening, no reliable test exists.

“There’s no foolproof way to predict someone’s ability to drive safely,” said Dennis McCarthy, co-director for the National Older Driver Research and Training Center at the University of Florida.

“Many seniors can and do drive well,” said Susan Samson of the Area Agency on Aging of Pasco-Pinellas.

Experts generally agree about the need for a road driving test. But even that is a snapshot in time that might not indicate whether a driver will forget to take his medication or lose mental alertness.

Additionally, more comprehensive state testing would be expensive and time-consuming.

“If you’ve lived in Florida for a long time, you know we revolt when the lines at the DMV get too long,” Samson said.

State driver license examiners are trained to look for signs of mental or physical impairment and can request the driver to take additional tests.

But mostly, the state relies on doctors, residents, family and neighbors to report potentially unsafe drivers.

In those cases, the state conducts its own examination and a medical board determines whether to pull a license.

Doctors can be crucial in determining a person’s ability to drive. In Florida, reporting is voluntary. Other states require it. California, for example, demands that medical professionals report all patients who have disorders that can cause “lapses of consciousness,” including Alzheimer’s disease. A physician who fails to report a required condition can be held liable for damages.

Pulling someone’s license is serious business, especially for the elderly, experts say.

Many older residents need a car to get groceries, fill prescriptions, continue social lives. Some drive when they shouldn’t because they feel they have no choice – a lack of public transportation, for example.

The loss of a driver’s license can lead to a downward spiral, as people stop eating, taking their medications and become isolated.

Giving up a license also comes with a psychological cost.

“Losing your ability to drive is one of the toughest things,” McCarthy said. “It tells us we’re not healthy, we’re not young, we’re not capable.”

Additionally, McCarthy points out that situations like Parker’s don’t happen often.

Older drivers are involved in far fewer accidents than other drivers, such as teens.

“There’s a tendency to sensationalize these types of incidents,” he said. “Although this one sounds very tragic, they are very few and far between.”

Parker was taken to Bayfront Medical Center for evaluation. He suffered only minor scrapes from the accident, but his dementia was cause for concern, Jockers said.

“He can’t even remember the name of the nurse that’s been taking care of him all day,” Jockers said.

Parker’s son, 66-year-old R. Thomas Parker Jr., spoke with police investigators on Thursday, relaying his father’s recent bouts of dementia.

The son could not be reached Thursday, and Jockers said he wished to be left alone. A daughter, who lives in Pennsylvania, declined to comment when reached by the St. Petersburg Times.

Their father is a longtime resident of the Mainlands of Tamarac, a 55 and older community off U.S. 19 in Pinellas Park. Neighbors said Parker and his wife, Hazel, moved there in the late 1970s and were active members of the community, attending dances and bingo. When his wife died in June 1998, Parker withdrew. About the only time people saw him was when he would drive by.

It seemed his one pleasure.

“That was the one thing he had,” said Jockers, “to get in his car and just drive for the sheer enjoyment of driving.”

John Logan, who perhaps knew Parker best, said about six weeks ago he noticed newspapers piling up in Parker’s driveway. He feared the worst but phoned his neighbor. To his relief, Parker answered.

“Oh, the newspapers. Yeah, I’ll have to get them,” Parker told Logan, the last conversation between the two men.

“He kind of sloughed it off and said, “I’ve been doing other things.’ “