The reasons that an insurer can deny your claim may differ depending upon both state laws and individual insurance company guidelines and policy terms. In general, misrepresentations, omissions, concealment of facts, or incorrect statements can lead to a claim denial. Using a vehicle without permission and creating the accident on purpose are a couple more ways.
Anything considered to be fraudulent or misrepresented as part of a claim will normally result in a claim being denied. In some situations if the car was damaged when used in a criminal act then a claim for said damage could be denied.
In California, failure to notify of policy claims can affect any policyholders of any form of insurance. A failure to notify issue typically arises when an insured person does not notify their insurance company in a timely manner. When this happens, the insurance company may deny the claim. In most cases, the insurance company must prove that it has been harmed or prevented from making an adequate investigation due to this delay.
According to the New Jersey Department of Banking and Insurance when you file a first party claim, you have a direct contract with your insurer that requires the company to fulfill all the conditions stated in your policy. However, the contract also places duties and requirements on you, the insured, when filing a claim. Therefore, you need to review that section of your policy often called "Conditions" or "Insured's Duties After a Loss."
The NJ DOBI also says that a proof of loss, as may be required by the insurance company, describing the date of the loss, how it happened, who was driving, and any other relevant information. If a proof of loss is required, your company could deny your claim if you fail to provide it.
Since there are other reasons an auto insurance claim can be denied and reasons may vary from one insurance carrier to the next, to be safe check with your insurance company to see what reasons they say a claim can be denied.