Defensive driving is the purchase of time and space
Not caution, and not slowness. It is arranging things in advance so that someone else's mistake stops being your emergency.
Defensive driving gets taught as an attitude, which makes it sound like a personality trait you either have or do not. It is more useful as a transaction. Every defensive habit buys you one of two currencies: time to notice and decide, or space to move into. Crashes happen when you have run out of both.
Once you see it that way, the individual techniques stop being a list to memorise. They are just different ways of buying the same two things.
Following distance is time, not distance
A gap measured in car lengths means nothing, because the same gap at 100 km/h is a fraction of the time it gives you at 50. Measured in seconds, it stays honest at any speed. The commonly taught NSW minimum is a three-second gap in good conditions, doubled when the road is wet, the light is poor, or you are behind something you cannot see past.
Pick a fixed object ahead, start counting when the car in front passes it, and see where you are at three.
Most drivers discover they are running at about one and a half seconds, and that it feels perfectly normal. Normal is the problem: one and a half seconds is roughly reaction time with nothing left over.
Four situations, and the move that comes before them
Each of these is a common crash type. The defensive move in every case happens earlier than the moment of danger.
Situation
The light ahead has been green a long time.
Earlier move
Treat a stale green as a light about to change. Ease off approaching it rather than arriving at speed and having to choose between a hard stop and running an amber.
Situation
You are passing a line of parked cars.
Earlier move
Move out a little and cover the brake. You are buying space from a door opening and time for a pedestrian stepping between vehicles, both of which you will not see coming.
Situation
A car is waiting to turn out of a side street.
Earlier move
Look at the front wheels, not the driver. Wheels move before a car does, and a driver looking straight at you can still pull out.
Situation
Traffic in the next lane is slowing and yours is not.
Earlier move
Assume there is a reason you cannot see yet, and slow before you find out what it is. The lane that keeps moving next to a queue is where the surprises live.
Being seen is half of it
Most of the above is about what you can see. The other half is being where other drivers are looking.
- Sitting in someone's blind spot is a choice. Be ahead of it or behind it, not in it.
- At an intersection, position so you are visible to the car waiting to turn, not hidden behind the vehicle beside you.
- Signal early enough to inform rather than announce a move already underway.
- In poor light or rain, headlights are as much about being seen as seeing.
What it is not
Defensive driving is not driving slowly. A driver well under the limit in the right-hand lane is generating risk, not reducing it, because everyone else is now making decisions about how to get around them.
It is also not the same as being a cautious person. Plenty of anxious drivers have very poor gaps, because anxiety tends to fix attention on the car immediately ahead rather than the situation forming three vehicles further on.
The road rules set the minimum standard. The current rules and penalties are published by the NSW Government, and they change from time to time.
Common questions
What is the three-second rule?
A way of measuring following distance in time rather than car lengths. Pick a fixed object ahead; when the vehicle in front passes it, you should not reach it before counting three seconds. It is the gap commonly taught in NSW for good conditions, and it is doubled in rain, poor light, or behind a vehicle you cannot see past.
Is defensive driving just driving slowly?
No. Speed well below the flow of traffic creates risk, because other drivers then make decisions about getting around you. Defensive driving is about buying time and space, which is mostly done through position, gaps and early observation rather than speed alone.
Do I need a defensive driving course to be a safe driver?
The habits matter more than the certificate. Following distance measured in seconds, scanning far enough ahead, and positioning so you can be seen are all trainable in ordinary lessons on ordinary roads.
Why look at the wheels of a car waiting to pull out?
Because wheels start moving before the body of the car does, which gives you slightly earlier warning. Eye contact is unreliable, since a driver can look directly at you and still pull out.
Does defensive driving help with the driving test?
The habits overlap heavily with what an assessor marks, particularly observation, following distance, gap selection and speed for the conditions. They are the same skills described in different language.
Senior driving instructor at Sydney South Driving School since 2013, with a Bachelor of Commerce and a professional background in accounting and five-star hospitality. More about Ashraf