Cycling, traffic safety, traffic justice, and legal topics; energy, transit and transportion economics
I was invited to attend a meeting 2/23/2026 pulled together by Kerry Wilcoxson (ADOT State Safety Engineer) where he invited folks from Arizona DHS (Dept of Health Services) as well as some other interested parties.
The topic being e-bikes and crash reporting. Which is of course getting all sorts of (mostly negative) attention, for understandable reasons. But the truth is we have very little data to go on… Continue reading “More about more about ebike crash reporting”
Executive Summary: You may have never heard of the MMUCC (Model Minimum Uniform Crash Criteria; a set of federal guidelines), it trickles down into every state’s motor vehicle crash reporting system. It’s somewhat analogous to the relationship between the UVC and state’s vehicle codes. The problem, I should say one problem, is non-motorists tend to get overlooked. One obvious example is delved into here — the “Manner of Crash”, e.g. angle, rear-end, sideswipe, etc. is ONLY defined when it involves two motor vehicles, leaving that data-field undefined when a crash is between a MV and bicyclist. Since bicyclists are vehicle drivers, the MMUCC should reflect that. Read on for a proposed change that’s on the table, and how you can vote/comment officially: Continue reading “MMUCC C9 Manner of Crash”
[Warning/correction not yet made: in the table below where it says MV-only, that’s not quite correct, it’s really incidents where no pedalscylists are involved. The MV-only calculations should also exclude pedestrians; this can be accomplished by saying u.eUnitType LIKE ‘PED%’ In the query below i corrected it but didn’t correct the table; the percentages don’t really change since there are relatively few ped crashes ]
Here is a breakdown of Collision Manner, and rates, for MV collisions (i.e. one or more MV, and not involving a ped or bicyclists) compared to bike-MV collisions.
The megatrends are that rear end collisions are, by far, the predominant manner of collision for MVonly crashes; wheres for bike-MV crashes this manner is quite infrequent — almost twelve times more frequent. For bike-MV crashes, the predominant manner is angle, i.e. so called “turning and crossing” movements (although left turn is broken out as a separate manner).
The 38% rate of REAR END crashes for MVs actually understates the rate — if you back out the number of SINGLE VEHICLE crashes; you see that nearly half of all multi-car collisions are REAR END(!). 38,499/(101,055 – 18,647) = 47%. Inattention? Does this mean that motorists actually are more attentive to same-direction traffic when it’s a bicyclist, compared to another motorist? hmmm.
+------------------------------+-------+--------+------+--------+-------------+ | eCollisionManner | MVonly| MVrate |bikeMV|bikerate|MV:bike ratio| +------------------------------+-------+--------+------+--------+-------------+ | REAR_TO_REAR | 287 | 0.0028 | NULL | NULL | NULL | | UNKNOWN_99 | 859 | 0.0085 | 40 | 0.0189 | 0.44973545 | | REAR_TO_SIDE | 895 | 0.0089 | 11 | 0.0052 | 1.71153846 | | SIDESWIPE_OPPOSITE_DIRECTION | 1244 | 0.0123 | 46 | 0.0217 | 0.56682028 | | HEAD_ON | 1438 | 0.0142 | 45 | 0.0212 | 0.66981132 | | OTHER_97 | 3160 | 0.0313 | 404 | 0.1905 | 0.16430446 | | SIDESWIPE_SAME_DIRECTION | 10727 | 0.1062 | 124 | 0.0585 | 1.81538462 | | LEFT_TURN | 11888 | 0.1176 | 189 | 0.0891 | 1.31986532 | | ANGLE_FRONT_TO_SIDE | 13411 | 0.1327 | 1194 | 0.5629 | 0.23574347 | | SINGLE_VEHICLE | 18647 | 0.1845 | NULL | NULL | NULL | | REAR_END | 38499 | 0.3810 | 68 | 0.0321 | 11.86915888 | +------------------------------+-------+--------+------+--------+-------------+ total num of MVonly crashes = 101,055. total num of bike-MV crashes = 2,121 source: 2012 ASDM