Lord Taylor of Gosforth, sitting in the Court of Appeal with Mr Justice Curtis and Mr Justice Gage, ruled that the four-and-a-half-year term imposed on a man who ran over and killed a 70-year-old while trying to steal his car was "unduly lenient". They ordered that Paul Dawes, 21, of Hartlepool, in Cleveland, should serve six years - the "least" sentence that could be imposed.
The judges then increased the sentence of Anthony Jackson, 24, of Holmewood in Bradford, West Yorkshire, from three years to five years after they heard he had killed a teacher while driving at speed the wrong way down a one-way street.
Both cases had been referred to the court for review by the Attorney General, Sir Nicholas Lyell, after the original sentences caused a wave of anger among relatives and the local communities.
Gary Waller, Tory MP for Keighley, said after the second hearing that the sentence imposed by Bradford Crown Court failed to take into account the fact that Parliament has decided on a 10-year maximum sentence for cases of this kind.
Jackson pleaded guilty in September 1995 to causing death by dangerous driving after he ran down John Lund, 42, who was out walking his dog near his home in Bradford.
Lord Taylor said Jackson, who had no driving licence or insurance, had turned off a main road at high speed into a narrow lane through "No Entry" signs where he struck Mr Lund and carried on without stopping. He then tried to make his car appear as if it had been stolen by smashing the steering lock and ignition, but confessed to police after his friends said they would report him.
Lord Taylor said: "The Attorney General is concerned about the level of sentence in this case. There is public concern generally about death by dangerous driving."
Dawes pleaded guilty to manslaughter and aggravated vehicle taking at Teesside Crown Court. Lord Taylor said the facts of the case were "disturbing". An elderly couple had returned from a dance club to their home in Hartlepool, and the husband, Robert Inchliffe, had left his car running in the driveway to help his wife into their home. Dawes jumped in the car and during his attempts to reverse out of the drive ran over Mr Inchliffe and killed him. He drove off at speed, leaving Mr Inchliffe in the road, and later abandoned the vehicle.
Dawes, who had previous convictions for shoplifting, taking vehicles, obstructing police and threatening behaviour, was driving while disqualified.
A police chief later criticised the "lenient sentence" given by the Court of Appeal to Dawes. Detective Chief Inspector Ray Mallon, who led the inquiry into the death, said: "In my view, the Court of Appeal paid no more than lip service to public opinion in relation to this crime.
"This is a disgraceful sentence for a crime as serious as this. It is another example of where the courts have let the public down. It seems the courts, on an extremely regular basis, fail to protect the public."