A march along Hallam Road calling for road duplication is being planned with organisers estimating several thousand protesters may attend.

Meanwhile, South Eastern Metropolitan MP Gordon Rich-Phillips and Casey Council said their calls for the Government to take action had gone unheeded for years.

But as the fingerpointing began, others feared the road toll will not be reduced until drivers change their behaviour.

Joel Brimble, 19, and Riyani Lowen, 16, both of Narre Warren South, and Anja Miler, 15, of Hampton Park, died after the Holden Commodore they were in collided with a Holden Statesman about 1.20am at the junction of Hallam and Ormond roads. A Frankston man also died and five others were injured.

Police investigating the carnage say speed and possibly alcohol played a role in the tragedy.

Although these were the first lives lost at the busy intersection, there have been 15 crashes there in the five years to December 2008 -- seven resulting in serious injury.

Reacting to the latest incident, Mr Rich-Phillips said: "I am aware that there may have been factors other than the state of the road that contributed to the tragic accident.

"However, the need to duplicate this section of road remains an underlying factor. I have raised the need to duplicate Hallam Road, especially the section between the South Gippsland Highway and Pound Road, twice in Parliament, the first time as far back as September 2005."

Mayor Geoff Ablett said the City of Casey wrote to the transport minister in November 2002, seeking a number of intersection upgrades, including the installation of traffic lights at the intersection of Hallam and Ormond roads.

"Since that time, the council has continued to advocate for the installation of traffic lights at the intersection at regular briefings with VicRoads - the most recent being in March 2009."

Hallam Road falls under VicRoads, which manages the state's arterial road network.

VicRoads' acting regional director for metropolitan south-east, Praveen Reddy, said the organisation was committed to improving safety at the intersection. "Safety improvements such as traffic lights have been earmarked for this intersection and VicRoads is investigating the best option for the site."

While traffic lights are high on the agenda, the Government last week said it had no plans to duplicate Hallam Road.

"Any upgrade proposals would be considered ... on a regionwide and statewide basis," a spokesman said.