Short answer: Down, probably to the lowest level in the three decades West Hollywood has been a city

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We can’t directly measure drinking & driving in West Hollywood, but we can analyze two proxies: arrests for driving under the influence (DUI) and collisions in which a driver was drinking. In both cases, we’re seeing drinking & driving through the eyes of the Sheriff’s Department, which makes the arrests and investigates the collisions.


Number of DUI arrests

West Hollywood DUI arrest statistics suggest that drinking & driving has been trending down sharply, both in recent years and over the past three decades. In the chart below, we see:

  • The number of arrests has fallen 92%, from 667 in 1986 to 51 in 2017, from two arrests a day to one a week
  • Last year had the fewest DUI arrests of any year since West Hollywood became a city
  • Although West Hollywood’s overall trend is down, DUI arrests have gone through up-and-down cycles, peaking most recently in 2011
  • The countywide trend generally mirrored West Hollywood through 2001, but the city’s numbers have dropped more than the county’s since then, despite the ups and downs

Notes: (1) A small percentage of the arrests were probably for drugs rather than alcohol. (2) We estimated countywide arrests for 1986 through 1989 based on statewide numbers. (3) The city was incorporated in 1984, but the first reported data is for 1986. Sources: US Department of Justice, Bureau of Justice Statistics, “Arrest in the United States, 1980-2014,” drawing data from the FBI’s Uniform Crime Reporting program; City of West Hollywood, semi-annual public safety reports; California Department of Motor Vehicles, “Annual Report of the DUI Management Information System,” various years; our analysis.


Number of drinking & driving collisions

We calculated two sets of collision numbers. Both show big downward trends in recent years. The broader set of numbers includes all collisions in which a driver had been drinking, regardless of the level of inebriation or the cause of the collision. That’s the red line labeled “drinking & driving” in the chart below.

Drinking & driving collisions dropped 75% in the last five years. The number went from roughly 240 in 2012 to about 60 in 2017. The new level is well below the level in every other year since 2001.

Note: (1) In some DUIs, the driver is under the influence of drugs rather than alcohol. We excluded collisions that didn’t involve alcohol from our “DUI as primary collision factor” number. (2) We couldn’t use the SWITRS data for 2013 and 2014 because it’s incomplete. We estimated “DUI as primary collision factor” for 2013 and 2014 using the Sheriff’s “DUI Traffic Collision Investigations” counts. We couldn’t fill in the gap in the “drinking & driving” series, so we just connected the dots between 2012 and 2015. Sources: California Highway Patrol, SWITRS database; City of West Hollywood, semi-annual public safety reports; our analysis.

The narrower set of numbers focuses on incidents in which a driver was legally drunk and that was the primary factor in the collision. The “DUI as primary collision factor” number fell 70% in the last five years. It went from almost 85 in 2012 to 25 in 2017.

We don’t have three decades of collision data, so we can’t say whether the collision numbers follow the same long-term pattern as the DUI arrest numbers. We do see a similar up-and-down cycle, with collisions and arrests both reaching recent highs around 2012.


When drinking & driving collisions happen

We expected drinking & driving to be concentrated in the late-night/early-morning hours of the weekend. The collision data confirmed it: Friday and Saturday nights had over 30% of the week’s drinking & driving collisions. A single hour — Saturday around 2:00 AM — had more than 5% of the collisions.

Of course, West Hollywood’s weekend isn’t limited to Friday and Saturday. Thursday and Sunday nights also had higher levels of drinking & driving.

Note: Data from 2001 to 2012 and 2015 to 2017. Sources: California Highway Patrol, SWITRS database; our analysis.

The collision data also shows that drinking & driving can happen at almost any time on any day. There were daily peaks at 2:00 AM. That one hour per day was responsible for almost 20% of drinking & driving collisions. The daily lows were generally around 6:00 AM.


Drinking & driving’s share of collisions

In the last three years, 11% of reported collisions involved drinking & driving. Alcohol was the primary collision factor in a third of those incidents, or 4% overall.

Half of the drinking & driving collisions happened late at night or early in the morning. They represented a quarter of all late-night/early-morning collisions.

Notes: In this chart, “late night/early morning” means the eight-hour period between 10:30 PM and 6:30 AM. Sources: Same as above.

From 2015 to 2017, drinking & driving collisions represented 14% of collisions with severe or fatal injuries. Focusing only on those three years, we can’t say with confidence that drinking & driving collisions were more likely to be severe/fatal. However, over the full 17 years of data, the relationship was statistically significant.

The rate of drinking & driving among pedestrian collisions — 10% — was about the same as the rate for collisions overall. Bikes were different. Only 5% of bike collisions involved drinking & driving. We suspect that’s because there weren’t many bicyclists on the streets late at night when drinking & driving was more prevalent.


http://wehobythenumbers.com/wp-content/uploads/2018/05/201805-dui-arrests-weho-county.jpghttp://wehobythenumbers.com/wp-content/uploads/2018/05/201805-dui-arrests-weho-county-300x300.jpgDavid WarrenPublic safetyTransportationdriving,los angeles county
Short answer: Down, probably to the lowest level in the three decades West Hollywood has been a city| We can't directly measure drinking & driving in West Hollywood, but we can analyze two proxies: arrests for driving under the influence (DUI) and collisions in which a driver was drinking....