An increase in drink-driving around Christmas is one of Britain's least admirable traditions.
And the police have set up extra patrols during the festive season to catch out those who are risking their lives - and the lives of others - by driving under the influence of alcohol and drugs.
West Yorkshire Police have already arrested more than 100 suspected drink drivers this month as part of their Not The Usual Suspects campaign and the figure is likely to rise as we get closer to Christmas and the New Year.
Drink-drivers don't have to be swerving across the road for police to spot them. There are more subtle signs that someone has had too much booze to drive legally and safely. It could also be that they're too tired to drive safely.
These are signs police look out for:
1) Headlights not on at night
2) Fog lights on when it isn't foggy
3) Speeding up and slowing down
4) Sudden acceleration
5) Sudden or erratic braking
6) Driving well below the speed limit
7) Drifting, swerving or weaving
8) Sudden or illegal turning
9) Turning within an unusually wide circle
10) Driving with face close to the windscreen
11) Driving too close to stationary objects
12) Tailgating
13) Slow (or no) response to traffic lights
14) Straddling two lanes or driving in the centre of the road
15) Driving with right tyres on the centre line
