Thailand drunk drivers face morgue work as punishment
"It is aimed to be a deterrent, a way to discourage people," police colonel Kriangdej Jantarawong said.
New Year celebrations start on Wednesday, with many people travelling long distances to visit family.
About 24,000 people die each year on Thai roads, according to the World Health Organization.
Only Libya has a greater number of fatalities per capita from road traffic accidents.
The government already sends some drunk and reckless drivers to work in hospital wards, Nontajit Netpukkana of the department of probation said.
But authorities decided that "the intensity" of morgue work would help give offenders a more explicit idea of the consequences of their actions, he said.
The cabinet approved the plan last week. Courts will be able to decide who deserves the punishment, the Bangkok Post reports.
Thailand's annual three-day New Year festival, known as Songkran, sees revellers throughout the country take part in water fights.
The government has assured tourists that despite severe drought the event will go ahead as usual.
Heavy drinking is common and the week of the festival is nicknamed the "Seven Deadly Days" because of a spike in road accidents.
The government earlier this year said the cars of drunk drivers could be impounded for the duration of the holiday.