You've probably seen it happen. You're driving your car and you come to a stop at the traffic lights. You're mindful of traffic infringement fines and public safety, then someone on a bike rides past you, straight through the red lights.
Riding through red lights is arguably the most hated cyclist behaviour - but why does it happen?
We conducted a national survey in which 2061 cyclists were asked: When you are riding do you stop at red lights?
Most (63 per cent) said yes, while more than a third (37 per cent) said they had ridden through a red light at some time.
Turning left against the red light was the most common reason cyclists gave for infringement (32 per cent), with safety and continued travel cited as the main motivations.
Some respondents considered it was safer to turn left against the red than to wait for the green light. Going through meant they would clear the intersection ahead of turning motor vehicles, considered safer than negotiating the turn with cars.
There was a perception that there was little risk from the crossing vehicle traffic as cyclists ride close to the kerb and do not enter the line of traffic.
Continued travel was also a benefit of this infringement type with some respondents treating some intersections as a give-way.
"The loop doesn't detect my bike". Almost a quarter of respondents (24.2 per cent) reported they infringed because they were unable to change the red light to green, as the inductive loop embedded in the asphalt did not detect their bike.
The way the respondents described this scenario followed a similar pattern.
On previous trips they had ridden to the intersection and there were no vehicles present. Despite riding over different sections of road, or waiting for long periods, they were unable to activate the signal change.
On subsequent trips, "based on that experience", the respondent would ride through the red light.
This typically occurred when riders were travelling early in the morning or later in the evening; but at some intersections, cyclists experienced this at at any time of the day.
This justification has been somewhat controversial in some Australian jurisdictions, with road authorities adamant that all cyclists can activate a signal change at all locations.
While this may be true, this has not been the experience for some cyclists who do not know the exact location they need to ride over to activate the signal change.
One simple solution is to clearly mark the location on the road that cyclists need to ride over to be detected by the sensor. For the effort of a stencil and a bucket of paint, this solution enables cyclists to actively engage in the road network and affirms to the community that road authorities recognise the legitimacy of cyclists as road users.
"There were no other road users." This reason is related to the previous one: without vehicles, cyclists couldn't change the light to green. But this one is also related to behavioural norms.
The presence of other road users can have a deterrent effect on the likelihood of infringement. Simply put, some cyclists are more likely to break the law if no one is watching.
"It was a pedestrian crossing." One in 10 respondents had infringed at a pedestrian crossing (10.7 per cent). This behaviour was seen as carrying little risk as the rider continues to travel straight and there is no interaction with other vehicles.
In addition, some cyclists infringed when they were riding across the pedestrian crossing, as they would cross as a pedestrian, effectively jay-cycling.
Interestingly, an individual's previous behaviour was also related to infringement. Respondents who had been fined for driving through a red light had 1.5-times higher odds of infringement when cycling, compared to those who had not been fined when driving.
There is definitely a role for enforcement to reduce the number of cyclists who ride through red lights. As with any other road user, cyclists need to be held accountable for illegal and potentially dangerous behaviour.
Increased red light compliance is likely to improve cyclists' image, and the attitudes some road users hold towards cyclists. But this is just part of the answer. There are gaps in our road network and perhaps we need to begin to consider the safety benefits for road users in relation to their characteristics, rather than blanketing everyone with the same rules as car drivers.
It may be it's safer for everyone if cyclists turned left at some intersections during the red light phase, and a trial of this could provide insights.
Adding symbols to indicate where cyclists need to ride to activate lights is a necessary and positive step to creating a road system that's cyclist-inclusive.
Marilyn Johnson is a research fellow at the institute of transport studies, Monash University.