The father of a teenager killed by a drink-driver in Belfast has said "the message is not getting through" after the PSNI revealed an increase in motorists arrested during their Christmas crackdown.
Police said some people caught under new legislation that allows random checks were so drunk they could barely stand.
Peter Dolan - whose son Enda was killed as he was walking to his student accommodation in 2014 - said the consequences of drink-driving are horrific, adding that his family were living a "daily nightmare".
The Co Tyrone man's comments come as hundreds of motorists in Northern Ireland were arrested in the last three weeks on suspicion of being over the limit as part of a PSNI crackdown on drink-driving.
A total of 241 motorists were arrested between November 24 and December 18 - up 1.7% compared with the same period last year. They include motorists who were unfit to drive, or who were unable or refused to give a sample.
Mr Dolan, from Killyclogher, said that tougher sentences need to be handed out to motorists convicted of drink-driving.
"It seems as if the message is not getting through to people and it's not surprising because there's no deterrent for anyone who drives under the influence," he said. "We have been campaigning this past 12 months for an increase in drink-driving and dangerous driving sentences. The consequences of drink-driving has been horrific for us. But people are not taking heed of the situation and that does not surprise me.
"I would tell people they need to think twice - get a taxi, a lift or some other way because we are now victims. Our son was horrifically and tragically killed and it is not a nice place to be. It has hit our local community and it has wide ranging consequences. We are paying the price.
"It's too selfish to take a chance, they need to think again.
"It's people's perception - but the bottom line is if you take a drink, leave the car at home. The message needs to be clear - don't take a chance because the consequences are horrific.
"We miss Enda terribly, there's an empty seat at the Christmas table now. It's unspeakable pain and for a lot of people it does not bear thinking about.
"We are living a nightmare and we have to try and get on with it as best we can. It has changed our lives dramatically and not for the better, but it's something we have to live with. Enda was an innocent pedestrian walking on the footpath and he was horrifically mowed down. That's what we have to live with."
This is the first year police have been able to carry out random vehicle checks thanks to new legislation introduced on November 24. "Northern Ireland is the first place in the UK to get this legislation," Chief Inspector Diane Pennington said.
"It means we no longer have to just suspect alcohol in a driver or that they have committed a traffic offence, which were previously the reasons why we could give them a breath test.
"Now we can put in place vehicle checkpoints and breathalyse every driver at that checkpoint."
In the first week of the campaign there was a 45% spike in arrests for drink-driving compared with last year. However, in subsequent weeks the numbers have been lower.
"We are taking this as good news," Chief Inspector Pennington added. "We think people are listening to our message and they are aware that there is a very strong likelihood they are going to be stopped."
A total of 700 vehicle checkpoints were put in place across Northern Ireland over the last three weeks and checks will continue right up until the end of the Christmas period.
"There will be officers out there on all days at the checkpoints," she said. "So if people are out there drinking and driving, they can expect to be stopped and they can expect to be caught."
She called on drivers to be vigilant over the festive period.
"What I would say to people is: we're all very good at planning our night out - who we're going out with, where we're going and what we're wearing. But sometimes we forget to plan how we are getting home. And there is no doubt that some of the drink-drivers we detect have ended up in that situation."