Mesa AZ | Personal Injury attorney Brian T. Allen discusses personal injury cases that involve more than one defendant in the following post:

Imagine the following scenario:

Anne is rear-ended by the car behind her while on the way to work. When it is safe to do so, Anne exits her vehicle to exchange information with the driver, and she notices three other cars stopped behind the one that hit her. Each of the three cars was also involved in the accident, and the drivers are all arguing about whose fault the accident was. Police arrive and Anne exchanges contact and insurance information with all four of the drivers. One month later, Anne is still experiencing pain in her neck and back, which started after the accident. She has to get medical treatment, and desires to receive compensation from the driver who caused the accident. However, she is unsure of which of the four drivers was at fault. Insurance claims are going nowhere, and Anne decides to hire an attorney and pursue a personal injury lawsuit against all four drivers. Is this a permissible lawsuit?

In Arizona, the answer is yes. Not all personal injury cases involve just two people: the injured (the plaintiff) and the injurer (the defendant). Some cases have one plaintiff and multiple defendants, and Arizona law provides for just resolution of such cases.

In cases with multiple defendants, the objective is not necessarily to find out who is solely responsible for the injury, although sometimes that will be exactly what happens. In most cases with multiple defendants, the assumption is that all defendants share fault, and the objective is to determine each defendant’s relative degree of fault.

For the most part, Anne’s hypothetical case would proceed like any other. If efforts at settlement fail, the case would go to trial. All four defendants would be present at trial, and each would get the opportunity to present their case. Anne would get the opportunity to present her case against each defendant. At the end of the trial the judge would instruct the jury on how to decide the case. At this point, Anne’s trial would differ from a more typical trial with only one defendant. Since there would be four defendants, the jury would receive special instructions regarding comparative negligence. These instructions would look something like the following (source: Arizona’s Revised Civil Jury Instructions):

If you find more than one defendant at fault for Anne’s injury, you must then determine the relative degrees of fault of all those whom you find to have been at fault. The relative degrees of fault are to be entered on the verdict form as percentages of the total fault for Anne’s injury. The fault of one person may be greater or lesser than that of another, but the relative degrees of all fault must add up to 100%.

Pursuant to those instructions, the jury will evaluate all the evidence, decide which of the four defendant’s was at fault – whether one, none, all four, or something in between – and then assign each defendant a percentage of fault in relation to the other defendants. All of the percentages added up must equal 100%. So, the jury might find Driver A 30% at fault, Driver B 20% at fault, Driver C 5% at fault, and Driver D 45% at fault.

After the determination of fault, damages remain an issue. Anne, of course, will receive 100% of the damage amount. The jury’s determination of the relative degrees of fault will be used to decide how much each defendant will owe. Based on the degrees of fault above, Driver A would owe 30% of the damage amount, Driver B would owe 20%, and so on.

This process allows for the just resolution of personal injury cases with multiple defendants in Arizona. If you should have further questions on this topic, or if you are considering a personal injury case with multiple defendants, 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 a Personal Injury Lawsuit with Multiple Defendants, 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.