Mesa AZ | Personal Injury attorney Brian T. Allen discusses the collateral source rule in the following post:

Imagine the following: Four months ago, a car hit you while you were riding your bike. You were seriously injured. You have finally been released from the hospital, and now you are preparing to start a personal injury lawsuit against the driver of the car. Based on your research, you think that you have a pretty good claim. You should be able to prove that the driver was negligent and that his negligence caused your injuries. You are ready to find an attorney. However, you do have one lingering question. Your insurance has already covered a fair amount of your medical bills. You wonder: If my insurance has already covered my medical bills, can I still seek money for my injuries from the driver of the car?

In all likelihood, the answer to this question will be yes. The controlling law here is called the Collateral Source Rule (let’s call it the CSR for short). The CSR allows an injured person to recover full compensation from the person responsible for the injury, even if another source (a collateral source) has already covered all or part of the costs stemming from the injury. However, the collateral source of compensation must be completely independent from the person responsible for the injury. So, money to cover your costs from insurance, your employer, a charity, etc., will not reduce the amount of damages you can seek from the responsible person. But any money received directly from the responsible person will limit the amount of money you can seek in a personal injury suit against the responsible person.

The CSR has a second effect. Not only does it prevent a jury from reducing your damages because insurance has already compensated you for part or all of your costs, it also prevents a jury from even hearing evidence of that compensation.

As an example, let’s imagine you are now in courtroom with your attorney at the personal injury trial for the aforementioned bike accident. You are on the witness stand, having just answered questions from your own attorney about the accident and your injuries. Now, the opposing attorney stands up and starts cross-examining you (asking you further questions). He asks you a few questions about the accident, which you answer. Then he asks you to answer a question about how much compensation you have received from your insurance to cover your injuries from the accident. Your attorney stands up and objects to the question, saying that the CSR prevents the jury from hearing such evidence. The judge upholds the objection, and you don’t have to answer the question. The judge rules this way because the CSR makes such evidence inadmissible in a personal injury case.

To summarize, the CSR does two things: 1) It prevents any reduction to an award of damages due to compensation from a collateral source that is independent from the defendant; and, 2) it makes evidence regarding such collateral compensation inadmissible.

One final thing about the CSR: it does not apply in medical malpractice cases. Per an Arizona statute (ARS 12 § 565), evidence of collateral compensation is admissible and relevant in medical malpractice trials; and juries can consider it when deciding upon damages.

This has been a brief, general overview of the Collateral Source Rule. Hopefully you have found it helpful. If you should have further questions on this subject, please contact us.


This blog should be used for informational purposes only. It does not create an attorney-client relationship with any reader and should not be construed as legal advice. If you need legal advice regarding The Collateral Source Rule, or any other personal injury, please feel free to contact Brian T. Allen at  480.461.5335,  log on to,  or contact an attorney in your area. Udall Shumway PLC is located in Mesa, Arizona and is a full service law firm. We assist Individuals, families, businesses, schools and municipalities in Mesa and the Phoenix/East Valley.