An MP says the voices of the families of the victims of a fatal "road race" crash must be heard in a campaign for tougher laws on dangerous driving.
Lesley-Ann Morgan's parents, Robert and Cynthia, outside court
Relatives of three young people killed in a minibus in Swansea are calling for longer sentences after such cases.
Swansea East's Sian James is among 150 MPs who wants a new offence of causing death by careless driving.
Two motorists were jailed on Tuesday for a total of 11-and-a-half years for causing death by dangerous driving.
Lesley-Ann Morgan, 21, her fiancÚ Neil Jenkins, 24, and friend Andrew Corbett, 19, died in June 2004 when the minibus they were in was hit by a BMW racing with a Volvo on Fabian Way, Swansea.
Volvo driver Christopher Churchill, 29, of Redditch, Worcestershire, was jailed for seven years, and Christopher Antonio, 20, of Swansea, for four-and-a-half years.
But the families said they should have been given the maximum 14 years' each in prison.
Robert Morgan, the father of Lesley-Ann, said robbers or fraudsters were given longer sentences than these two motorists, and said he would campaign for a change in the law.
Lesley-Ann Morgan, with fiancÚ Neil Jenkins; friend Andrew Corbett
"Four-and-a-half years for one and seven years for another is a real kick in the guts for us. I believe the actual charge should have been a minimum of manslaughter," said Mr Morgan.
Lesley-Ann and Neil were due to marry only weeks after the accident.
"Unfortunately the life she had in front of her has been taken away from her," said Mr Morgan.
"She never really fulfilled the potential she was showing in her job and in her everyday life.
"I'm annoyed by the fact that it was stated in court that Mr Churchill wanted to get home - so did my daughter and all the other members in the minibus that night. They will never come home."
Neil's younger brother Steven said: "I haven't just lost a brother, I've lost a sister in law to be who I was really close with.
"We are all disgusted about the sentence but there's not much we can do."
Ms James signed a House of Commons motion in July calling on the government to establish a new offence of death by careless driving. It followed an MPs' report highlighting its absence from the statute book.
Ms James told BBC Radio Wales serious questions needed to be asked as the families faced their own "life sentences".
"I want to work with them - I want to help them articulate their views because it's important their voices are heard," she told Good Morning Wales."
Volvo driver Christopher Churchill and BMW driver Christopher Antonio
Of the need for a new offence, she said: "It's something that we in Westminster feel very strongly about."
At Swansea Crown Court, Churchill admitted dangerous driving, but had denied causing death by dangerous driving. He was convicted of the first charge by a jury.
Antonio, who was 18 at the time of the crash, admitted causing death by dangerous driving.
Both were also banned from driving: Churchill for nine years and Antonio for seven years.