Crash data – medical events
Cover sheet
Page 1 of 6
and drugs 2023-2025
OIA-21856 - Crash data - medical events and drugs 2023-
2025
Report Date:
5/05/2026
Data extract date:
5/05/2026
Requester:
Nigel Gray
Request:
A. Medical Event Crashes (2023, 2024, 2025) [...]
please provide:
The number of fatal crashes where the primary contributing factor was recorded as a
‑
medical event.
The number of serious injury crashes where the primary contributing factor was a
‑
medical event.
The number of minor injury crashes where the primary contributing factor was a medical
‑
event.
The number of fatal crashes removed from the official road toll dataset because they
were determined to be caused by a medical event.
The exact Police or CAS factor codes, definitions, or descriptors used to classify a crash
as a medical event.
The number of cases currently coded as “suspected medical event” or equivalent where
coronial findings are pending.
B. Drug Related Crashes (2023, 2024, 2025) For each of the last three calendar years,
please provide:
‑
The number of fatal crashes where drugs were recorded as a contributing factor.
The number of serious injury crashes where drugs were recorded as a contributing
‑
factor.
The number of minor injury crashes where drugs were recorded as a contributing factor.
The number of fatal crashes where both alcohol and drugs were contributing factors.
The factor codes, definitions, or descriptors used to classify drug involvement.
‑
The number of cases initially coded as “pending toxicology” that were later updated to
“drug related.”
under the Official Information Act 1982
C. Classification and Data Handling Procedures Please provide:
The internal Police guidance, instructions, or criteria used to determine when a crash is
classified as:
‑
a medical event
‑
drug related
alcohol related
excluded from the official road toll
Any procedures or thresholds used when updating crash records following coronial
findings or toxicology results.
Released
Source database:
Crash Analysis System (CAS)
Report produced by: Statistical Services
Peer reviewed by:
Statistical Services
Crash data – medical events
Cover sheet
Page 2 of 6
and drugs 2023-2025
Please note the fol owing concerning the data contained in this spreadsheet:
• This data is provided from the road traffic crash database; Crash Analysis System (CAS) version 2.14.2.
• NZ Transport Agency Waka Kotahi (NZTA) maintains CAS which is updated once a Traffic Crash Report
(TCR) is received from New Zealand Police sometime after the crash.
• Data is limited to all crashes for the years 2023 to 2025 as recorded in CAS to date - as at 5 May 2026.
• A crash, to be recorded in CAS must have occurred on a road. The CAS definition of a road is any street,
motorway or beach, or a place to which the public have access with a motor vehicle, whether as of right or
not - for example, a public car park.
• Due to New Zealand Police reporting time frame and subsequent data processing there is a lag from the
time of a crash to full and correct crash records within CAS.
1982
• Due to the nature of non-fatal crashes, it is believed that these are under-reported, with the level of under-
reporting decreasing with the increasing severity of the crash.
Act
• Data relating to fatal, serious injury and minor injury crashes is usually recorded in CAS within one working
day of the NZTA receiving it from New Zealand Police. Data relating to non-injury crashes is usually
recorded in CAS within six weeks of receipt.
• Crash severity is the severity of the worst injury in the crash. There may be more than one injury in a
crash, so the crash and injury tables may have different numbers.
• The cause of a crash cannot necessarily be attributed to any one factor (for example, fatigue) as a crash
may have multiple factors.
• Where Alcohol/Drugs are a contributing factor to a crash, this factor has been separated into either
"Proven" or "Suspected". A factor is only counted once against a crash.
Information
• Where a crash has both a proven and suspected factor against it, only the factor "Proven" is counted.
• CAS is continually updated as new information is provided, therefore data regarding injuries, and factors
attributed to crashes, may change from previous releases.
• Due to an increased focus by Police to update TCRs with additional information, particularly the outcome
of blood test results, the numbers of crashes with Alcohol and/or Drugs proven or suspected may change
from other data released previously.
Official
the
For further information, please contact [email address]
under
Released
Crash data – medical events and drugs 2023-2025
Data1
Page 3 of 6
This information must be read in conjunction with the Caveats on the first page of this spreadsheet.
1982
2023-2025 crashes
Injuries from crashes 2023-2025
Year
Fatal crashes
Serious injury
Minor injury
Non-injury
Act
crashes
crashes
crashes
Total crashes
Year
Deaths
Serious injuries Minor injuries
Total injuries
2023
305
2,086
8,568
20,548
31,507
2023
342
2,459
11,307
14,108
2024
249
2,090
8,306
18,689
29,334
2024
291
2,465
10,999
13,755
2025
260
2,062
8,220
18,467
29,009
2025
272
2,423
10,976
13,671
Total
814
6,238
25,094
57,704
89,850
Total
905
7,347
33,282
41,534
2023-2025 crashes involving a medical event*
Injuries from crashes involving a medical event* 2023-2025
Year
Fatal crashes
Serious injury
Minor injury
Non-injury
crashes
crashes
crashes
Total crashes
Year
Deaths
Serious injuries Minor injuries
Total injuries
2023
4
61
287
418
770
2023
4
65
339
408
2024
6
77
317
419
819
2024
7
87
399
493
Information
2025
3
76
320
385
784
2025
3
85
401
489
Total
13
214
924
1,222
2,373
Total
14
237
1,139
1,390
* Crashes involving a 'medical event' are defined as those where one or more of the following factors were coded as contributing factors in CAS:
• Other il ness
• Sudden il ness
• Physical impairment
• Defective vision
Official
• Medical il ness (not sudden)
• Mental il ness (depression, psychosis)
• Impaired ability due to old age
• Other disability
the
under
Released
Crash data – medical events and drugs 2023-2025
Data2
Page 4 of 6
This information must be read in conjunction with the Caveats on the first page of this spreadsheet.
1982
2023-2025 crashes where 'Drugs proven' was a contributing factor
Injuries from crashes where 'Drugs proven' was a contributing factor 2023-2025
Year
Fatal crashes
Serious injury
Minor injury
Non-injury
Act
crashes
crashes
crashes
Total crashes
Year
Deaths
Serious injuries Minor injuries
Total injuries
2023
105
202
173
72
552
2023
117
294
375
786
2024
93
220
177
103
593
2024
114
322
374
810
2025
90
276
218
114
698
2025
95
393
446
934
Total
288
698
568
289
1,843
Total
326
1,009
1,195
2,530
• Data is limited to crashes involving drugs.
• Drugs means 'Drugs proven' was a contributing factor to the crash.
2023-2025 crashes where both 'Drugs proven' and 'Alcohol test above limit or test refused' were
Injuries from crashes where both 'Drugs proven' and 'Alcohol test above limit or test
contributing factors
refused' were contributing factors 2023-2025
Year
Fatal crashes
Serious injury
Minor injury
Non-injury
crashes
crashes
crashes
Total crashes
Year
Deaths
Serious injuries Minor injuries
Total injuries
Information
2023
38
15
16
1
70
2023
41
36
43
120
2024
23
12
13
7
55
2024
27
23
27
77
2025
43
21
19
6
89
2025
45
46
56
147
Total
104
48
48
14
214
Total
113
105
126
344
• Data is limited to crashes involving both drugs and alcohol.
• Drugs and alcohol means both 'Drugs proven' and 'Alcohol test above limit or test refused' were contributing factors to the crash.
Official
the
under
Released
Crash data – medical events and drugs 2023-2025
Factors1
Page 5 of 6
This information must be read in conjunction with the Caveats on the first page of this spreadsheet.
Crash Factors
The determination of the primary cause of a crash is complex and often crashes have multiple factors contributing to them.
Where multiple factors have been identified as contributing to a crash, it is difficult (if not impossible) to identify which of the factors was the primary cause of the crash.
1982
It is also difficult to determine if any one factor had a stronger contribution to the injury outcome of the crash. For example, a crash has had the following contributing factors: alcohol test
above limit or test refused, did not stop at steady red light, other lost control, speed at temporary speed limit, worn tread on tyre, and road under construction or maintenance.
Al these factors contributed to the crash and no one factor can be confidently identified as the primary cause or for its impact on the injury outcome of the crash.
Act
Factors are counted once against a crash - that is, two fatigued drivers count as one fatigue crash factor.
The numbers under the year headings are the number of crashes where that factor was a contributing factor to the crashes for that year. The Total is the sum of all the factors contributing to crashes.
Because a crash may have multiple factors there wil be more total factors than crashes resulting in factors totalling more than 100% of all crashes
Where Alcohol and/or Drugs are a contributing factor to a crash, this factor has been separated into either "Proven" or "Suspected".
Where a crash has both a proven and suspected factor against it, only the factor "Proven" is counted.
Factors contributing to 2023-2025 crashes
Factors contributing to 2023-2025 crashes involving a medical event*
Road safety factor groups
2023
2024
2025
Total
Road safety factor groups
2023
2024
2025
Total
Alcohol/Drugs both proven
75
63
93
231
Alcohol/Drugs both proven
1
1
2
Alcohol proven
3,364
2,795
2,651
8,810
Alcohol proven
20
30
24
74
Drugs proven
489
542
610
1,641
Drugs proven
25
34
32
91
Alcohol/Drugs both suspected
109
90
55
254
Alcohol/Drugs both suspected
3
3
Information
Alcohol suspected
1,019
914
734
2,667
Alcohol suspected
19
23
12
54
Drugs suspected
265
281
242
788
Drugs suspected
10
11
8
29
Disabled, old age or il ness
831
872
836
2,539
Disabled, old age or il ness
770
819
784
2,373
Failed to give way or stop
5,950
5,473
5,449
16,872
Failed to give way or stop
31
28
27
86
Fatigue
1,432
1,378
1,290
4,100
Fatigue
19
18
11
48
Incorrect lanes or position
6,902
6,415
6,478
19,795
Incorrect lanes or position
187
198
204
589
Miscellaneous factors
2,333
2,207
1,870
6,410
Miscellaneous factors
21
21
13
55
Official
Overtaking
613
700
543
1,856
Overtaking
1
1
2
Pedestrian factors
630
663
616
1,909
Pedestrian factors
6
9
10
25
Poor handling
5,431
4,942
4,823
15,196
Poor handling
148
146
134
428
Poor judgement
3,917
3,600
3,131
10,648
Poor judgement
24
19
17
60
the
Poor observation
9,531
8,899
8,660
27,090
Poor observation
26
38
35
99
Position on Road
3,233
3,062
3,148
9,443
Position on Road
123
143
129
395
Road factors
2,983
2,552
2,446
7,981
Road factors
7
14
12
33
Travel Speed
5,035
4,085
3,793
12,913
Travel Speed
36
42
26
104
Vehicle factors
1,432
1,301
1,110
3,843
Vehicle factors
7
8
3
18
Weather
1,120
782
940
2,842
Weather
3
6
8
17
TOTAL factors
56,694
51,616
49,518
157,828
TOTAL factors
1,484
1,612
1,489
4,585
under
* Crashes involving a "medical event" are defined as those where one or more of the following factors were coded
as contributing factors in CAS:
• Other il ness
• Sudden il ness
• Physical impairment
• Defective vision
• Medical il ness (not sudden)
• Mental il ness (depression, psychosis)
• Impaired ability due to old age
• Other disability
Released
Crash data – medical events and drugs 2023-2025
Factors2
Page 6 of 6
This information must be read in conjunction with the Caveats on the first page of this spreadsheet.
Crash Factors
The determination of the primary cause of a crash is complex and often crashes have multiple factors contributing to them.
Where multiple factors have been identified as contributing to a crash, it is difficult (if not impossible) to identify which of the factors was the primary cause of the crash.
1982
It is also difficult to determine if any one factor had a stronger contribution to the injury outcome of the crash. For example, a crash has had the following contributing factors: alcohol test
above limit or test refused, did not stop at steady red light, other lost control, speed at temporary speed limit, worn tread on tyre, and road under construction or maintenance.
Al these factors contributed to the crash and no one factor can be confidently identified as the primary cause or for its impact on the injury outcome of the crash.
Act
Factors are counted once against a crash - that is, two fatigued drivers count as one fatigue crash factor.
The numbers under the year headings are the number of crashes where that factor was a contributing factor to the crashes for that year. The Total is the sum of all the factors contributing to crashes.
Because a crash may have multiple factors there wil be more total factors than crashes resulting in factors totalling more than 100% of all crashes
Where Alcohol and/or Drugs are a contributing factor to a crash, this factor has been separated into either "Proven" or "Suspected".
Where a crash has both a proven and suspected factor against it, only the factor "Proven" is counted.
Factors contributing to 2023-2025 crashes where 'Drugs proven' was a contributing factor
Factors contributing to 2023-2025 crashes where both 'Drugs proven' and 'Alcohol test above limit or
test refused' were contributing factors
Road safety factor groups
2023
2024
2025
Total
Road safety factor groups
2023
2024
2025
Total
Alcohol/Drugs both proven
71
57
89
217
Alcohol/Drugs both proven
70
55
89
214
Alcohol proven
0
Alcohol proven
0
Drugs proven
481
536
609
1,626
Drugs proven
0
Alcohol/Drugs both suspected
0
Alcohol/Drugs both suspected
0
Information
Alcohol suspected
0
Alcohol suspected
0
Drugs suspected
0
Drugs suspected
0
Disabled, old age or il ness
29
37
38
104
Disabled, old age or il ness
1
1
2
Failed to give way or stop
62
55
67
184
Failed to give way or stop
6
2
4
12
Fatigue
45
43
39
127
Fatigue
6
4
1
11
Incorrect lanes or position
109
108
157
374
Incorrect lanes or position
18
12
19
49
Miscellaneous factors
66
77
64
207
Miscellaneous factors
15
11
11
37
Official
Overtaking
22
20
21
63
Overtaking
3
1
4
Pedestrian factors
2
1
2
5
Pedestrian factors
0
Poor handling
135
146
159
440
Poor handling
26
17
30
73
Poor judgement
61
60
77
198
Poor judgement
7
5
9
21
the
Poor observation
85
80
85
250
Poor observation
7
5
5
17
Position on Road
135
152
159
446
Position on Road
18
18
23
59
Road factors
46
49
41
136
Road factors
7
4
5
16
Travel Speed
188
162
175
525
Travel Speed
40
23
38
101
Vehicle factors
44
33
40
117
Vehicle factors
7
3
10
20
Weather
19
17
14
50
Weather
4
1
2
7
TOTAL factors
1,600
1,633
1,836
5,069
TOTAL factors
235
162
246
643
under
Released
Document Outline
