A back of fag packet analysis...
According to the DfT ...
The number of vehicle miles per year is about 300-350bn (I know you specified "cars", but I'm doing "vehicles")
The number of cycle miles per year is about 3-5bn
So roughly 100 times more vehicle miles than bike miles. (I'd have thought it would be more, maybe I have it wrong)
So if bikes/cyclists cause more than 1% of the number of deaths due to vehicles/drivers they will be more deadly per unit distance travelled.
Annual road deaths are around 1,700
So if more than 17 of these are caused by cyclists, and the rest are due to vehicle drivers then bikes are more deadly per unit distance travelled.
I think we can cap the number of pedestrians killed by cyclists per year at about 1. Each time it happens it is headline news. Let's be generous and say 5. I'll set motorists killed by cyclists at 0. Meaning that the balance of 12 fatalities would have to be cyclists killed either by themselves, or by other cyclists.
It's not impossible - it could even be true. But even if it was true it wouldn't be terribly meaningful. After all many vehicles accrue lots of distance on long uneventful motorway stretches.
Maybe per unit travelling time would be more meaningful? Lets assume that cars go at 4 times the speed of bikes on average (10mph vs 40mph average) So that would mean that bikes/riders would need to kill more than 4% of the number of deaths due to vehicles/drivers to be more deadly per unit travelling time. Which I think highly unlikely.
All my base figures and logic are guaranteed to be flawed.
View attachment 602651
https://assets.publishing.service.g...d-traffic-estimates-in-great-britain-2020.pdf