In July 2025, the California Assembly passed a bill seeking to expand the scope of ignition interlock devices (IIDs) as they pertain to Chapter 2 of the Vehicle Code. The main objective of Assembly Bill 366 is to reduce driving under the influence (DUI) situations by making the installation of IIDs mandatory in all convictions. As the Assembly voted on AB 366, law enforcement agencies across the state were scheduling checkpoints and patrols to deal with the surge of summer DUI cases. A recent analysis showed that 16% of all car accidents in the city of Modesto were alcohol related and the NHTSA attributes nearly a third of all traffic deaths to drunk driving.
DUI Activity Spikes During California Summers
Many regions of California are blessed with excellent year-round weather; however, summer is extra special across the Golden State. Many residents and visitors enjoy driving to the beaches and national parks. Others drive to music festivals and other fun summer events. Those who stay in their communities can enjoy barbecue grilling and backyard cookouts in the sunshine, often driving to the store for beer runs.
There’s no question that California summers are fun and magical; unfortunately, they are also more dangerous on the roads, streets, and freeways of the Golden State. According to the California Office of Traffic Safety, the most active months in terms of DUI-related accidents and deaths are June, July, and August. This trend, which has been on the rise since 2017, is one of the most challenging for state transportation safety officials, and it explains the rationale behind AB 366.
When it comes to seasonal driving patterns, the summer-DUI nexus in California is driven by the following factors:
* More vehicles on the road: While traffic in some of the most populous metropolitan areas is lighter because schools and colleges are on summer break, there’s a higher number of young and inexperienced drivers on the road. Summer also brings more visitors to California, and many of them choose to drive. A higher traffic density means more drivers are on the road, and many of them could be under the influence at any time.
* Major holidays: Summer is packed with major holidays that are often celebrated with cold beverages. Sales of liquor, beer, and wine skyrocket in California from Memorial Day to Labor Day, a period that some traffic safety researchers call the “100 deadliest days of summer.” This is when long holiday weekends turn into the most dangerous days for DUI situations.
* Social gatherings and the vacation mentality: Something is always happening in California during the summer. Parties, barbecues, music festivals, and road trips often feature a festive atmosphere punctuated by alcoholic beverages. The risk of a DUI increases as more people drive to and from these gatherings, particularly when they are driving in unfamiliar areas. There’s also the more relaxed and vacation-oriented mindset that makes drivers pay less attention to their surroundings.
Increasing Summer Driving Safety and Avoiding DUIs
If you know you will be drinking, why not plan ahead and arrange for transportation? Booking an Uber ride or arranging for a designated driver to take you home are wise summer planning strategies. If you are hosting a party, serve non-alcoholic beverages beyond beer and liquor.
When you see someone who has been drinking try to drive, don’t be afraid to speak up. Offer to drive them yourself, set up an Uber ride, or do whatever it takes to stop them from getting behind the wheel. This type of intervention can save lives.
Don’t rely on smartphone apps that estimate blood alcohol content based on consumption. Good judgment is always better than any app you can install from the Apple App Store or Google Play. You can use the apps for fun or to get a general sense of your state; nonetheless, you should not drive if you have doubts.
Should you get in a summer accident involving DUI in California, don’t forget to call 911, get a medical evaluation, and consult with a personal injury law firm.
