David and Karen Longstreet are channeling their physical and emotional pain over the loss of their daughter at the hands of an alleged drunk driver into a crusade to keep impaired motorists off the road.

Carrying photographs of 6-year-old Emma, the Lexington couple went to the State House on Tuesday to urge lawmakers to crack down harder on DUI.

“Our loss is beyond words,” said David Longstreet, who still wears a sling on his right arm from the accident. “This is something no parent should have to go through.”

The accident occurred Jan. 1, 2012, as the Longstreet family — which includes three sons — traveled to church to start a new year.

“We’re living hell on earth,” Karen Longstreet said. “Every day I wake up and say the pain is so much.”

The measure the Longstreets want the General Assembly to approve would require more motorists convicted of driving while intoxicated — including some first-time offenders — to have ignition interlock devices installed on their vehicles.

That equipment is a breathalyzer that stops anyone from driving after consuming even a small amount of alcohol, with a reading of .02 preventing a vehicle from starting.

Currently, a reading of .08 is considered a legal sign of intoxication in South Carolina.

The measure is less than some anti-DUI crusaders prefer. It would require the devices for those convicted of DUI with a reading of .12 and higher, a compromise mollifying some critics.

The devices now must be used by repeat offenders.

The Longstreets are putting a face on a proposal — nicknamed Emma’s law — that supporters say will help reduce drunken driving.

“They are taking a nightmare and trying to make a change that would prevent other families from going through this,” said Sen. Joel Lourie, D-Richland, a sponsor of the bill.

But others lawmakers consider making use of the equipment mandatory for some first-time offenders onerous.

“People deserve forgiveness for a first mistake,” Sen. Gerald Malloy, D-Darlington, said of those who aren’t involved in accidents that injure or kill others.

There also are hurdles to overcome regarding how drunken drivers can evade the devices by using the vehicles of spouses, relatives, friends and employers.

Meanwhile, charges are pending against Billy Hutto of Gilbert, the driver whom police say rammed into the side of the van in which the Longstreet family rode. Hutto has a previous DUI conviction, Lexington police have said.

In addition to lobbying the Legislature, the Longstreets pass out purple wristbands with Emma’s name and a message against driving after drinking.

Emma was a first-grader at Midway Elementary interested in French, soccer, gymnastics, and arts and crafts.

Her parents plan a golf tournament April 25 at Golden Hills in Lexington to raise money for the school and for anti-DUI efforts.

Their three sons, ages 9 to 12, survived the accident without injury but miss their sister, the couple says.

“We can’t save our daughter,” David Longstreet said, “but doing this can help prevent others from suffering what we have.”

By the numbers

318

Traffic deaths in South Carolina in crashes involving a drunk driver in 2011, the latest year analyzed

150

Reduction in deaths estimated for 2011 if use of the proposed ignition interlock equipment is expanded to some first-time DUI offenders

17

States that require such devices for all convicted drunk drivers

Source: Mothers Against Drunk Driving