If you go out drinking at night and get in the car to drive the next morning, you may end up with more than a hangover.

Devon and Cornwall Police force is cracking down on people who are still over the limit "the morning after" as part of the Christmas drink-drive campaign.

The number of arrests for drink-driving offences in Cornwall and Devon has gone up slightly in the past year.

Chief Inspector Ian Aspinall, said drivers are often not aware of just how long it takes alcohol to clear from the blood.

It's down to each individual to know when they are clear of alcohol

Chief Inspector Ian Aspinall

He said: "Alcohol is still in people's system the morning after, but people who are seasoned drinkers do not realise they are over the limit."

He said that he expected an increase in arrests as a result of the clampdown.

"It's down to each individual to know when they are clear of alcohol.

"If they have any doubts they should refrain from driving."

All it does is cause paranoia

Austin Williams

But the independent Transport Research Group has questioned the need for a campaign aimed specifically at the festive period.

It says more people die as a result of drink driving at other times of the year than at Christmas.

Spokesman Austin Williams said: "You would have thought that we should be celebrating rather than having a mean-spirited approach at this time of year.

"All it does is cause paranoia and you begin to worry about drinking a glass of sherry.

"I think everyone is fully aware of the dangers of drink driving, and the majority of people respond to that.

"Most people in accidents are well over the limit and they do not respond to some naff campaign."

Last Christmas, of more than 15,000 drivers breath-tested in the UK, 8% were over the limit - an increase of almost 1% on the last festive season.