Head Injury Claim: The First Steps That Shape a California Case

If you or someone with you has hit their head and is showing symptoms right now — loss of consciousness, repeated vomiting, a worsening headache, confusion, slurred speech, seizure, weakness in the limbs, or fluid draining from the nose or ears — call 911 or go to an emergency room. That is a medical question, not a legal one, and it comes first. This page is not medical advice; the CDC, Cleveland Clinic, Mayo Clinic, and Johns Hopkins Medicine publish far better material on the medical picture than any law firm can.

What follows is the legal side: how a head injury claim works in California whatever caused it, why these claims are documented differently from other injuries, and the deadlines that apply.

Key Points

• Get evaluated the same day. Symptoms after a head impact commonly appear later, and a gap between the incident and the first medical record is the most common argument raised against these claims.
• Who you report to depends on where it happened — that step is not the same for a collision, a fall on a business’s property, and an injury at work.
• These claims often lack an objective imaging finding, which makes them the hardest injury category to document and the easiest for an insurer to dispute.
• The injured person is frequently the least reliable reporter of their own symptoms. Observations from family and colleagues carry unusual weight here.
• You do not have to have struck your head for a brain injury to occur.
• Do not sign anything an insurer sends early. A release ends the claim permanently, including for what nobody knew about yet.

Where Head Injuries Happen, and What Changes

The claim process is broadly the same whatever the cause, but the responsible party and the deadline are not.

• A vehicle collision. The at-fault driver, and sometimes an employer or vehicle owner. California also imposes reporting duties that apply regardless of fault — see below.
• A fall or an incident on someone’s property. The property owner or occupier, where a condition of the premises was unsafe. Report it to the owner or manager and ask that an incident report be made.
• An injury at work. Workers’ compensation is generally the exclusive remedy against your employer, but a civil claim may still be available against a third party who contributed — a contractor, an equipment manufacturer, another driver.
• An assault. A civil claim can run alongside any criminal case, and does not depend on a conviction.
• A defective product, including protective equipment that failed to do its job.

Which route applies also determines which deadline you are working to, and they differ substantially. Our page on whether you can sue for a brain injury sets out the four tracks.

The First Steps

Get evaluated, the same day

Even if you feel fine. This is both the medically sensible thing and, if a claim follows, the single most valuable thing you can do for it — a record created close in time to the incident is the answer to almost every causation argument an insurer will make.

Report it, to the right person

After a collision, call the police. On a business’s premises, tell the owner or manager and ask for a written incident report. At work, report it to management immediately — workers’ compensation has its own notice requirements. In each case, ask for a copy of whatever gets written down.

California also imposes reporting duties after a collision that apply regardless of fault: a written report to law enforcement within 24 hours where anyone was injured, and an SR-1 report to the DMV within 10 days where there was any injury, a death, or property damage over $1,000. Our page on what to do after a car accident covers those.

Document while it is fresh

Photographs of the scene and of any hazard, the names and numbers of witnesses, and what you remember of the sequence. Memory for this degrades within hours, and a contemporaneous note is worth more later than a reconstruction.

Why These Claims Are Different

Most injury claims are argued about degree. Head injury claims are frequently argued about existence.

A fracture appears on an X-ray. A milder brain injury often does not appear on standard imaging at all, which means the claim rests on clinical assessment, symptom reporting, and evidence of changed function rather than on a picture. Insurers know this, and the defence is predictable: normal scans, subjective complaints, and some other explanation for the symptoms — stress, sleep, a pre-existing condition, or ordinary life.

The consequence is that these claims are won or lost on documentation built early, and on evidence most people do not think to gather.

Delayed Symptoms and the Gap Argument

Symptoms after a head impact frequently show up hours or days later. Adrenaline masks a great deal at the time, and cognitive changes in particular tend to surface once the person tries to return to ordinary demands — work, driving, managing a household.

That delay is medically unremarkable and legally expensive. Every day between the incident and the first medical record is a day an insurer will use to argue the injury came from something else. It is the most common causation argument in this category.

The Injured Person Is Often the Worst Historian

This is the point that most distinguishes a head injury claim, and it is barely discussed anywhere.

Where an injury affects memory, concentration, or self-awareness, the person living with it may not accurately perceive or report what has changed. They may insist they are fine. They may not notice that they are losing track of conversations, taking three times as long at tasks, or becoming uncharacteristically short-tempered. In some cases they genuinely cannot notice.

So the most valuable evidence in these claims often comes from other people. A spouse describing what mornings look like now. A manager describing work that used to take an hour. A friend describing someone who stopped going out. Contemporaneous observations from people who knew the person before are harder for an insurer to dismiss than the injured person’s own account, and they are usually never collected because nobody thought to ask.

You Do Not Have to Hit Your Head

A brain injury can occur without any impact to the head. “I never hit my head” is a sentence people say at the scene, repeat to their doctor, and then find quoted back at them months later.

The medical sources are the ones to rely on. The CDC’s HEADS UP guidance describes concussion signs following a bump, blow, or jolt to the head or body, and notes that signs and symptoms may not show up right away — they can take hours or days to appear.

What matters on our side is narrower: the absence of a head impact is not a legal answer to the claim. Insurers raise it; it does not by itself defeat anything. Describe what happened to your body accurately and let a clinician decide what it means.

What Builds the Record

• Prompt evaluation, and follow-through on referrals rather than stopping when the acute phase passes.
• Specialist assessment where symptoms persist. Where cognitive effects are in issue, formal neuropsychological evaluation is often what moves a claim from assertion to evidence.
• Consistent symptom reporting across every provider, so the record does not contradict itself.
• Before-and-after evidence from other people, gathered while recollection is fresh.
• Employment records showing changed duties, reduced hours, errors, or accommodations.
• Specific functional detail rather than general complaint — what can no longer be done, and for how long.

A note on symptom journals, which are widely recommended online. They can help, but anything created for a claim is discoverable and will be read closely by the other side. A sporadic or exaggerated journal does more damage than none. If one is kept, it should be honest, including about good days.

Do Not Sign Early

Insurers sometimes make an offer before the extent of a head injury is understood, and in this category that is a particular risk because the trajectory is uncertain for months.

A settlement release ends the claim permanently, including for consequences nobody knew about at signing — California releases routinely include an express waiver of the statutory protection that would otherwise preserve unknown claims. There is no mechanism for reopening a claim because symptoms turned out to persist. Our page on settlements covers what a release does, and what a fair offer is measured against — which is not a published range.

The same caution applies to recorded statements and broad medical authorisations requested early. Neither is something you are required to provide before getting advice.

Deadlines, and What Happens If Capacity Is Affected

Most California injury lawsuits must be filed within two years of the injury under Code of Civil Procedure section 335.1. Medical negligence, workplace, and public entity claims run on different timelines — see our page on suing for a brain injury.

Code of Civil Procedure section 352 provides that where a person entitled to bring an action was, at the time the cause of action accrued, either under the age of majority or lacking the legal capacity to make decisions, the time of that disability is not counted as part of the limitations period. Three things to understand:

• The bar is high. California presumes that people have the capacity to make decisions. A brain injury — even a serious one — does not by itself establish a lack of legal capacity. This is a legal standard about the ability to understand and manage one’s affairs, not a medical diagnosis.
• It does not rescue a claim against a public entity. Section 352 expressly does not apply to actions against a public entity or public employee where a claim has to be presented under the Government Claims Act. So where a city vehicle, a transit agency, or a dangerous roadway may be involved, the much shorter government claim timeline runs regardless of the injured person’s condition. That is a trap in exactly the cases where it matters most.
• Do not rely on it as a plan. Whether tolling applies is decided later, on evidence, by a court.

If Someone Cannot Manage Their Own Claim

Where an injury leaves someone unable to handle a legal matter, California courts can appoint a representative to bring and manage the claim on their behalf, and settlements in those circumstances are subject to court oversight rather than being agreed privately.

Families in this position are usually also dealing with medical decision-making, income loss, and care arrangements at the same time. It is worth getting advice early rather than after a deadline has become urgent.

What Can Be Recovered

Depending on the evidence, the categories that may apply include past and future medical care, rehabilitation, lost income, reduced earning capacity, the cost of care and assistance, and non-economic harm including loss of enjoyment of life. Severe cases involve future costs that have to be projected rather than totalled from bills already received.

Our economic damages and pain and suffering pages cover the two categories, and how much of a settlement actually reaches you after fees, costs, and medical liens is on the settlements page.

What no page can do is tell you what a claim is worth. Published averages pool cases with nothing in common, and value depends on the documented injury, the apportionment of fault under pure comparative fault, and the insurance actually available. Where an incident is fatal, a wrongful death claim follows its own rules.

Head Injury Claims on the Peninsula

Our office at 15 North Ellsworth Avenue, Suite 105, San Mateo, CA 94401 handles injury claims across San Mateo County, and civil matters for this area are generally heard in the San Mateo County Superior Court. These injuries arise in collisions involving cars, motorcycles, bicycles, and pedestrians, in falls, and from defective products. More about the office is on our San Mateo page.

How Vaksman Khalfin Can Help

Our brain injury practice handles these claims from the medical documentation through to resolution: making sure the right assessments happen and are in the record, gathering the before-and-after evidence from people who knew the person, identifying every policy that may apply, protecting the filing deadlines rather than relying on tolling, and dealing with the insurers while a family deals with treatment. Where a claim cannot be resolved, our page on brain injury lawsuits explains what litigating one involves.

The practice is led by Alan D. Khalfin, admitted in California. We handle injury matters on a contingency-fee basis: there is no upfront attorney’s fee, and attorney’s fees are owed only if we recover compensation for you. Case costs are a separate category from attorney’s fees, and how both are handled is set out in the written fee agreement we go through with you before anything is signed. Initial consultations are free.

To speak with a California personal injury attorney, call 650-250-0705 or schedule a free consultation. Related reading: our California personal injury guides.

Reviewed by Alan D. Khalfin, Partner and Managing Attorney, Vaksman Khalfin, PC (admitted in California). Last reviewed: 09/08/2026