Roberts said a lower alcohol limit would make people more aware of their limitations before they drove, but he also wanted tougher punishments for drink-drivers.
"Six months' disqualification he said, "is pathetic," .
A 2012 Ministry of Transport poll released this month shows 40 per cent of respondents favour lowering the blood-alcohol limit from 80mg to 50mg per 100ml. One in five people want the limit lowered to zero.
Half the drivers who admitted driving while slightly intoxicated also favoured a lower limit.
The 1667 respondents were also asked how many standard drinks drivers should be allowed. Four out of five thought the limit should be two or fewer drinks during the hour before they got behind the wheel.
Thirty-six per cent said drink-driving laws were not very effective; 37 per cent thought the risk of being caught drink-driving was small.
The report found attitudes to drink-driving had remained steady for three years. The Government has conducted its own two-year review of drink-drive statistics, which it says is still not complete.
Transport Minister Gerry Brownlee did not agree to an interview this week.
In a statement, spokeswoman Rose Chamberlain said: "Officials are compiling and reviewing data and it is expected that Ministers will have something to consider before the end of the year."
Lees-Galloway said the Government was dithering and out of step with public opinion. "There is a public mood to do it. The evidence is there."