California Motorcycle Law: What Every Sacramento Rider Should Know About a Personal Injury Case
California’s statutory framework for motorcycle operation is more developed than most states’, and several provisions have direct consequences for how a motorcycle accident case is litigated. Understanding the relevant law is essential to recognizing when the defense is making a real argument and when it is just bluster.
Lane Splitting Is Legal: Vehicle Code § 21658.1
California is the only state that has expressly codified lane splitting at the state-statute level. Vehicle Code § 21658.1, effective January 1, 2017, defines lane splitting as “driving a motorcycle that has two wheels in contact with the ground, between rows of stopped or moving vehicles in the same lane, including on both divided and undivided streets, roads, or highways.” The statute also authorizes the California Highway Patrol to develop and publish educational guidelines.
What lane splitting being legal means in litigation: a defendant cannot argue that the fact of lane splitting was itself wrongful or negligent. The only question is whether the specific lane-splitting maneuver, in context, was done with reasonable care. A motorcyclist filtering through stopped traffic at low speed in normal commute conditions is doing something lawful and expected; an insurer’s attempt to portray it as reckless is a tactic, not a legal argument.
The Helmet Law and Damages: Vehicle Code §§ 27802 and 27803
California requires drivers and passengers on motorcycles, motor-driven cycles, and motorized bicycles to wear a safety helmet that meets the standards set under § 27802. The DMV’s implementing regulations require compliance with Federal Motor Vehicle Safety Standard No. 218 (49 C.F.R. § 571.218), and helmets must be conspicuously labeled with the manufacturer’s certification of federal compliance.
The question of how helmet non-use or non-compliance affects damages is more nuanced than some sources suggest. California has not enacted a statutory helmet-defense provision comparable to the seatbelt-defense provision in Vehicle Code § 27315(j). At the same time, California has not categorically barred all evidence relating to helmet use either. The case law on safety-equipment non-use, including the California Supreme Court’s decision in Horn v. General Motors Corp., 17 Cal.3d 359 (1976), reflects courts’ historical reluctance to allow broad comparative-fault reductions based on a plaintiff’s failure to wear safety equipment. The seatbelt-defense framework was later modified by statute (§ 27315(j)) for seatbelt cases; no parallel statute exists for motorcycle helmets.
In practice, defendants in motorcycle cases sometimes attempt to introduce evidence that a rider’s failure to wear a compliant helmet was a substantial factor in causing or aggravating specific head injuries. Whether such evidence is admissible turns on the specific factual record, including expert testimony on whether a helmet would actually have prevented the particular injury sustained. The California Supreme Court’s discussion in Clemente v. State of California, 40 Cal.3d 202 (1985), illustrates the kind of causation evidence courts require. The takeaway is that helmet evidence is not an automatic blanket reduction, but it is also not an automatic exclusion. The fight is on the specific facts.
Motorcycle Licensing: Vehicle Code § 12804.9
California issues two motorcycle license classes. Class M1 authorizes operation of any two-wheel motorcycle or motor-driven cycle. Class M2 is more limited, authorizing motorized bicycles, mopeds, and motor-driven cycles. A rider with an M1 endorsement may operate any vehicle in the M2 category without additional examination. Applicants under 21 must complete a California Motorcyclist Safety Program novice course to obtain either endorsement.
Equipment Requirements That Come Up in Litigation
Vehicle Code § 27801 sets handlebar height limits (hands on grips no more than six inches above shoulder height). Section 27800 requires a properly secured rear seat and footrests for any passenger. Sections 25650 and 25650.5 require functioning headlamps and, for motorcycles built after January 1, 1978, automatic headlamp activation when the engine starts.
California’s Minimum Auto Insurance: Vehicle Code § 16451
Effective January 1, 2025, California’s minimum auto liability coverage requirements increased to $30,000 per person, $60,000 per accident, and $15,000 in property damage. These minimums apply equally to drivers of cars and motorcycles, since motorcycles are “motor vehicles” under California law. Voris v. Pacific Indem. Co., 213 Cal.App.2d 29 (1963). A further increase to $50,000/$100,000/$25,000 is scheduled for January 1, 2035.
The relevance for motorcycle cases is significant. Even with the increased minimums, the policy limits available from an at-fault driver who carries only minimum coverage are usually not enough to cover serious motorcycle injuries. Identifying additional sources of coverage is one of the most important things a motorcycle attorney does early in a case.
Uninsured and Underinsured Motorist Coverage
Your own UM/UIM coverage is often the most important source of compensation in a motorcycle case where the at-fault driver carried only minimum policy limits or no insurance at all. Insurance Code § 11580.2 governs UM/UIM bodily-injury coverage in California. In hit-and-run cases involving bodily injury, the statute generally requires three things: actual physical contact between the insured and the unidentified vehicle, a police report within 24 hours of the accident, and a sworn statement to the insurer within 30 days. A separate property-damage UM provision, Insurance Code § 11580.26, has its own structure (including a 10-business-day reporting requirement for property damage). Insurance Code § 11580.23 separately addresses notice requirements in actions filed against an uninsured motorist.
Whether your case fits the physical contact requirement turns on the specific facts. The California courts have construed “physical contact” relatively broadly. In Pham v. Allstate Insurance Co., 206 Cal.App.3d 1193 (1988), the court held that the contact requirement is met when an object carried or thrown by a vehicle strikes the insured. The deadlines for police reporting and the sworn statement are strict, however, and we strongly encourage anyone in a hit-and-run scenario to involve law enforcement immediately and consult an attorney without delay.
Howell and Medical Specials
The California Supreme Court’s decision in Howell v. Hamilton Meats & Provisions, Inc., 52 Cal.4th 541 (2011), limits recovery of past medical expenses to the amounts actually paid or accepted in satisfaction of those bills, rather than the gross amounts billed. Corenbaum v. Lampkin, 215 Cal.App.4th 1308 (2013), extended that limitation to evidence of future medical specials. This matters for case valuation: the “amount billed” number is not the recoverable number, and a competent attorney works with the actual paid amounts.
Conspicuity and Comparative Fault
Insurers in motorcycle cases routinely raise “conspicuity” arguments: the motorcyclist was wearing dark clothing, was in a blind spot, was lane splitting, was at a relative speed differential, or otherwise was not as visible as the defendant thinks they should have been. Under California’s pure comparative fault rule from Li v. Yellow Cab Co., 13 Cal.3d 804 (1975), any percentage of fault assigned to the rider reduces the recovery, but does not bar it. The fight in most motorcycle cases is over allocation: an experienced motorcycle attorney challenges each conspicuity argument with the legal duty of the other driver to look out for what is plainly visible, the actual facts of the lookout (was the defendant on a phone, was their view actually obstructed, did they have prior similar near-misses), and expert testimony where appropriate.
