General Insurance Principles (P&C Lens)
Property and casualty insurance rests on a small set of legal and economic ideas that explain why an insurer is willing to pay thousands of dollars on a claim in exchange for a few hundred dollars of premium. This chapter walks through what makes a risk insurable, the special features of an insurance contract, the timing rule for insurable interest in property (very different from life insurance), how the principle of indemnity controls payouts, and the clauses (subrogation, other-insurance, coinsurance, deductibles) that an adjuster actually applies at the loss site. Master these eight sections and you have covered roughly five percent of the exam plus the foundation every later P&C chapter assumes.
Risk, Hazards, and What Makes a Risk Insurable (DICE)
Risk is the uncertainty about whether a loss will occur. Insurers will only write pure risk, the chance of loss or no loss with no possibility of gain (a house may burn or may not burn). Speculative risk, which includes a chance of gain, is uninsurable; you cannot buy a property policy on a horse race or a stock trade. A peril is the cause of loss, such as fire, theft, or windstorm. A hazard is a condition that increases the chance or size of a loss and falls into four families: physical (a frayed extension cord, a wood-shake roof in a fire zone), moral (an insured who plans to torch their own building for the claim), morale or attitudinal (carelessness that grows because the insured knows they are covered, such as leaving a bike unlocked), and legal (a jurisdiction known for plaintiff-friendly juries or strict statutes). To be commercially insurable, a pure risk must also pass the DICE test used on the California P&C exam: the loss must be Definite in time, place, and amount; the cause must be Identifiable; the probability must be Calculable so an actuary can set a rate; and it must be an Economic loss that is not catastrophic to the carrier when many policies are pooled.
Law of Large Numbers and Adverse Selection
An insurer can charge a fair premium only because of the law of large numbers, a statistical rule stating that as the number of similar exposure units observed grows, actual loss experience converges on the predicted average. One frame house's chance of burning in a year is hard to predict, but the loss rate on a million similar frame houses is highly predictable, which is why rating bureaus collect loss data across the state. The pool must be made up of homogeneous exposures, meaning risks that share construction, occupancy, protection, and exposure characteristics; mixing a fireworks factory into a homeowners pool destroys the prediction. Adverse selection is the opposite force: people and businesses who know they have an above-average chance of loss apply for coverage more aggressively than the general public. A landlord whose tenants just started cooking meth has a stronger reason to buy a fire policy than the average landlord. Underwriting — inspections, prior-loss reports, credit-based insurance scores where permitted, replacement-cost estimators, and the right to decline or surcharge — is the carrier's defense against adverse selection.
Elements of a Valid Contract and the Special Features of Insurance
Every insurance policy is first a contract, so it must contain the four classic contract elements: offer and acceptance (the application is usually the offer; the insurer's issuance of the policy at the quoted terms is the acceptance); consideration (the applicant's premium plus statements in the application, exchanged for the insurer's promise to pay covered losses); legally competent parties (of legal age and mental capacity, and the carrier must be authorized to write that line in California); and legal purpose (you cannot insure an illegal grow operation or a property held to commit fraud). Insurance contracts then carry four distinctive features tested heavily on the exam. They are aleatory, meaning the amounts exchanged are unequal and depend on chance — the insured may pay $800 and collect $400,000 or pay $800 and collect nothing. They are unilateral, meaning only the insurer makes an enforceable promise after the premium is paid; the insured cannot be sued for breach for failing to keep paying. They are contracts of adhesion, drafted entirely by the insurer and offered take-it-or-leave-it, so ambiguities are construed against the insurer. They are conditional, meaning the insurer's duty to pay is triggered only when the insured satisfies conditions such as paying premium, giving prompt notice of loss, and cooperating in the investigation.
Utmost Good Faith, Representations, Warranties, and Concealment
Insurance is a contract of utmost good faith (uberrimae fidei), meaning each party is entitled to rely on the truthful disclosures of the other because only the applicant truly knows the condition of the insured property or the history of past claims. California codifies this through three doctrines. A representation is a statement believed true at the time made, included in or based on the application; it must be true in all material respects, and a material misrepresentation lets the insurer rescind the policy. A warranty is a stricter promise written into the policy itself, such as a protective-safeguards warranty that a sprinkler system will stay operational; breach of warranty can void coverage even if the breach did not cause the loss. Concealment is the silent failure to disclose a material fact the applicant knows and that the insurer does not, such as a recent denial by another carrier or a prior arson conviction. Under California law, concealment, whether intentional or unintentional, entitles the injured party to rescind. Fraud, an intentional misstatement made to induce coverage or payment, is grounds for rescission and may be referred to the CDI Fraud Division.
Insurable Interest in Property — The Time-of-Loss Rule
Insurable interest is the financial stake a person must have in the subject of insurance for the policy to be legally enforceable. Without insurable interest, the contract is a wager and is void as against public policy. The California rule for property insurance is critically different from the rule for life insurance and is a frequent exam trap. For life insurance, insurable interest must exist only at the time the policy is issued. For property and casualty insurance, insurable interest must exist at the time of the loss; it is not enough that the insured owned the property when the policy was bought. The classic example is a homeowner who sells the house but forgets to cancel the policy. If the house then burns, the seller has no insurable interest at the time of loss and collects nothing — the policy will not pay the seller, and it does not transfer to the buyer without the insurer's consent. Common sources of insurable interest in property include outright ownership, a security interest such as a mortgage or lienholder, a leasehold interest, a bailee's responsibility for customers' goods, and a contractual obligation to insure.
Indemnity, Subrogation, and Valuation (ACV vs. Replacement Cost)
The principle of indemnity, the dominant idea in property insurance, says the insured should be put back in the same financial position they were in just before the loss — no better and no worse. Insurance is not meant to be a source of profit. Two valuation methods dominate California P&C policies. Actual Cash Value (ACV) is the most common and is generally defined as replacement cost at the time of loss minus depreciation for age, wear, and obsolescence; a fifteen-year-old roof is paid at a fraction of a new roof. Replacement Cost (RC) coverage pays the cost to repair or replace with new property of like kind and quality, with no deduction for depreciation, usually subject to a coinsurance requirement and a holdback that releases the depreciation only after the insured actually rebuilds. Subrogation is the partner of indemnity: after the insurer pays the insured, the insurer steps into the insured's shoes and may pursue the negligent third party who caused the loss. Subrogation prevents the insured from collecting twice and shifts the cost back to the at-fault party. The insured must not impair the insurer's subrogation rights, for example by signing a release of liability with the at-fault driver before reporting the claim.
Other Insurance, Coinsurance, and the 80% Rule
When more than one policy covers the same property loss, the indemnity principle still applies — the insured cannot collect the full loss from each insurer. Other-insurance clauses describe how the carriers share. A pro-rata clause makes each insurer pay in the proportion that its limit bears to the total insurance in force, so a $300,000 limit and a $700,000 limit on the same building pay 30% and 70% of any covered loss. A contribution-by-equal-shares clause makes each carrier pay equal dollar amounts up to its limit, used mostly in commercial liability. An excess clause makes one policy primary and the other pay only after the primary limit is exhausted, common in umbrella and auto. Coinsurance is a different concept that lives inside a single property policy: it requires the insured to carry insurance equal to a stated percentage (commonly 80%) of the property's replacement cost at the time of loss. If the insured is underinsured, the insurer pays only a proportional share of any partial loss, calculated as (Insurance Carried ÷ Insurance Required) × Loss, minus any deductible. The clause is a financial incentive to insure to value and a frequent source of exam math.
Limits, Deductibles, and the Valued vs. Open Policy Distinction
Every property policy contains a limit of insurance, the maximum dollar amount the insurer will pay for a covered loss. Limits may be stated per occurrence (the most the carrier pays for any one event) or as an aggregate (the most the carrier pays in total during the policy period, typical in commercial liability). An open policy, the standard property form, pays the actual cash value or replacement cost of the loss up to the limit, with the limit only as a ceiling; the insured must prove the amount of loss. A valued policy, used for hard-to-value items such as fine art, antiques, or under California's Valued Policy concepts for certain total losses, pays the stated value without further proof of amount. Deductibles are the portion of each loss the insured pays before coverage applies, and the form matters. A flat deductible is a fixed dollar amount per loss, such as $1,000. A percentage deductible is a percent of the dwelling limit, common for California earthquake and hurricane coverages, so a 10% deductible on a $500,000 home is $50,000. A franchise deductible pays nothing until the loss exceeds a threshold, then pays in full; a disappearing deductible shrinks as the loss grows and disappears entirely above a stated amount. Higher deductibles lower premium because the insured retains more of the small-loss frequency.
Last updated: May 2026