It was the day after Christmas. A hulking tractor-trailor, flying down a New England highway, rammed an economy-sized Dodge Dart from behind - demolishing half of the silver car and pitching the other half and the family inside onto the road.

Kenneth and Frances Nathanson of Bethesda recovered from their injuries, buried their daughter, and began an investigation into their own accident.

They found out that the driver of the truck had lost his license several times for violations and accidents in many states.

Yet, liked millions of other, the trucker kept driving by jumping state lines to get a new, valid license. The trucker's cross-state maneuver worked because the National Driver Register isn't working.

"If our program had worked the way it should have his daughter (Kamy Nathanson) would be alive," said Brian Connell, chief of the National Driver Register.

The Register is a section of the federal Department of Transportation which was designed to act as a store-house of information on Americans who have had their licenses suspended or revoked in any state.

The program is not effective, according to Connell, primarily because all the states are not fully participating.

Connell said New York, California, Florida and Puerto Rico, jurisdictions with over 20 per cent of the nation's population do not fully participate in the register.

It absolutely baffles me that Americans raise hell about people getting stabbed, shot and drowned while these drivers commit murder like clockwork every day and no one gets excited," said Connell.

Connell said the register turns up the names of 750 people each day who have had their license revoked or suspended in one state and are seeking a new license elsewhere. Based on that figure and the knowledge that many states are not using the register fully, Connell estimated that there are millions of drivers on the roads who have gotten their current licenses by slipping across state lines.

The register receives 6,000 reports of suspensions or revocations daily from states and makes inquiries on 90,000 license applications a day.

Connell said his estimates do not include persons who falsify their identification when crossing state lines to apply for another license after losing their first license.

A spokesman for the National Highway Users Association offered another example of a driver who was able to continue to drive and eventually kill because of poor communications between state licensing agencies.

Last March 9, in Lynchburg, Va. a truck hit a school bus while it was stopped on the side of the road. Three children were killed. The truck driver was a North Carolina man who had licenses in at least two states, North Carolina and Florida.

On his North Carolina license the man had over 25 moving traffic violations and some accidents. Authorities refused to disclose the number of accidents on his record. His North Carolina license had been suspended at least five times.

The truck driver's Florida license had three moving traffic violations on it. One of the violations occurred in Arkansas while his North Carolina license was suspended.

Officials in Florida and North Carolina said they didn't know of the man's other license or his other violations.

The Highway Users Federation estimates that there are 10 million drivers without licenses or with invalid licenses on American roads, out of 129,100,000 drivers in the nation.

A 1976 study by the National Highway Administration of 197 fatal accidents in 1973 found that 11 of the drivers involved in those accidents were driving with suspended or revoked licenses. Another 21 people involved had had their licenses suspended or revoked in the past.

A joint study by the Insurance Institute for Highway Safety and John Hopkins University School of Hygience and Public Health found that five percent of the drivers involved in fatalk accidents in Maryland during 1970 and 1971 did not have valid drivers licenses when their accidents happened.

Connell said the first step in any crackdown on Americans who ignore licensing regulations will have to be improvement of the register.

Not only do states fail to participate in the register, but they also limit the register, but they also limit the register's access to state records through privacy laws.

Massachusetts and Pennsylvania will inform the register if a driver has had his license suspended or revoked but they won't disclose the reason because of their privacy laws.

"It is unbelievable," said Connell. "We have public records covered by the privacy act instead of being covered by the freedom of information laws."

Connell said all states will refuse to issue a license to a person once they are informed that the person is under suspension or has had his license revoked by another states.

The problem, Connell said, is creating a system that will ensure that the states learn about suspension and revocations in other states.

Connell warned that federal laws requiring states to fully participate in the register would not solve the register's problems but would involve the register and the states in a tangle of legal problems.

Connell said a survey found that 80 per cent of the states want instant electronic communication with the register and they want more information stored in the register.

Currently it takes 24 hours plus mailing time for the register to answer the 90,000 inquiries it receives daily.

"There are going to have to be some changes," said Connell after citing the case of two truck drivers who had licenses despite a combined record of 49 driving offenses. In two separate accidents in 1975 and 1976 they killed nine people, injured ten and did $31,000 in damage, he said.

Meanwhile the Nathansons have continued their mission against the bad driver who stays on the road by testifying before Congress, and talking to Department of Transportation administors about improving the driver register.

"We've committed ourselves because the problem these drivers cause are hidden problems," said Nathanson. "Even the families of the victims are not aware of the problem unless they stop calling what happened an accident and start taking a deeper look at who was involved and what really happened.

"We can't bring our daughter back," said Nathanson, "and we can't save everyone else from being killed but we might save someone else's child."