MONTREAL -- Politicians and police in Quebec are promising to do better after an investigator blamed the government's response system for the debacle on a city highway last March that left 300 motorists stranded after a major snowstorm.

Authorities underestimated the severity of the problems and communicated poorly with one another, Florent Gagne concluded in his report released Friday.

The Transport Department "lamentably failed in its job," Gagne wrote, adding provincial police "lacked initiative."

No one person is to blame, however, because the system didn't work, said Gagne, a former head of the Quebec provincial police and an ex-deputy transport minister.

In particular, Transport Minister Laurent Lessard can't be blamed for inaction because critical details about the events weren't brought to his attention, Gagne said.

The "main reason" for the crisis was due to the Transport Department's command centre not doing its job, he told a news conference.

"There were not enough personnel," Gagne said. "No bosses were there, the computers weren't working properly. The patrols on the road were not feeding the centre (with information) as they usually do. Information didn't go up the ladder to the hierarchy of the Transport Department."

Hundreds of drivers were left stranded on Montreal's Highway 13 on March 14 after the massive storm blanketed the city with about 40 centimetres of snow.

Some drivers spent the night in their vehicles while others abandoned their cars and left on foot after waiting hours in vain for help.

Lessard responded to the report with a statement saying he would "put in place all the necessary means to improve the ability of the department to respond to emergencies so that a similar situation doesn't occur again."

The provincial police's media department released a statement saying it put in place a new 24-hour monitoring service following the snowstorm. It added the force is also conducting an internal investigation into its response to the storm.

"Disciplinary measures could be taken after the conclusion (of the investigation)," it stated.

Gagne recommended an "exhaustive review" of the Transport Department's response system.

He also suggested the department undertake the regular practice of conducting "unadvertised checks" to see if the emergency response system works.

"This never happened in the department," Gagne said. "So they should (check) once in a while to see if the people in charge are doing their jobs (properly)."