Proving that an accident caused your injuries is usually the make-or-break issue in a Nevada personal injury case. In plain terms, you must connect the crash, fall, or other incident to your medical condition in a way a jury (or an insurance carrier evaluating the claim) can accept as more likely true than not.
Below is how Nevada law approaches causation, plus the practical evidence that tends to prove it.
1) What you must prove in Nevada: “cause” is part of negligence
In a Nevada negligence case, you must prove the defendant’s negligence was a proximate (legal) cause of your damages. Nevada jury instructions commonly frame this as requiring proof that the defendant’s negligence was a proximate or legal cause of harm.
Nevada case law describes proximate cause as a cause which, in natural and continuous sequence, produces the injury and without which the injury would not have occurred. Taylor v. Silva, 96 Nev. 738, 615 P.2d 970 (1980). Mahan v. Hafen, 76 Nev. 220, 351 P.2d 617 (1960). Drummond v. Mid-West Growers Coop. Corp., 91 Nev. 698, 542 P.2d 198 (1975).
Also important, the defendant’s negligence does not have to be the only cause. It must be a cause, and in many factual settings Nevada decisions discuss the idea that negligent conduct can be a substantial factor in bringing about the injury. Taylor v. Silva, 96 Nev. 738, 615 P.2d 970 (1980).
If the defense argues you were partially at fault, that is typically addressed through Nevada’s comparative negligence statute, which can reduce (and in some cases bar) recovery depending on the apportionment of fault. NRS 41.141. Taylor v. Silva, 96 Nev. 738, 615 P.2d 970 (1980).
2) Medical causation often requires expert testimony in Nevada
Many injury disputes are not about whether an accident happened, but whether the accident caused the medical diagnosis being claimed (disc herniation, radiculopathy, meniscus tear, concussion symptoms that persisted, surgery necessity, future care, and similar issues).
Nevada appellate decisions emphasize that when causation is a medical question beyond ordinary lay understanding, you typically need competent medical expert testimony, and opinions must be expressed to a reasonable degree of medical probability, not mere possibility. Morsicato v. Sav-On Drug Stores, Inc., 121 Nev. 153, 111 P.3d 1112 (2005). Williams v. Eighth Judicial Dist. Court, 127 Nev. 518, 262 P.3d 360 (2011).
A common practical takeaway is this: if your injury claim requires a physician to explain “how” and “why” the mechanism of the accident caused the condition, your case becomes much stronger when your treating doctor (or a retained expert, if needed) clearly documents causation and prognosis using probability-based language.
3) The evidence that most directly proves causation
Insurance carriers and defense lawyers usually test causation by attacking the timeline, your medical history, and whether your symptoms match the event. The best evidence responds to those exact attack points.
A strong Nevada causation record often includes:
A. A clean timeline
- Date/time of incident (police report, incident report, 911 records if applicable).
- Immediate symptoms, even if you did not go to the ER the same day.
- First medical visit and what you reported then.
- Continuity of complaints (for example, neck pain with radiating symptoms consistently reported over time).
B. Early, consistent medical history
Statements you make for purposes of medical diagnosis or treatment are generally treated differently than statements made for litigation, and they often carry credibility with juries. NRS 51.115.
C. Objective findings when available
- Imaging results (X-ray, MRI, CT).
- EMG/NCV testing for radiculopathy.
- Range-of-motion findings, positive orthopedic tests, neuro deficits.
D. A doctor’s causation statement stated as probability
If a physician documents that the accident “more likely than not” caused the injury or aggravated it, that goes directly to the Nevada “reasonable medical probability” requirement described in Nevada case law. Morsicato v. Sav-On Drug Stores, Inc., 121 Nev. 153, 111 P.3d 1112 (2005). Williams v. Eighth Judicial Dist. Court, 127 Nev. 518, 262 P.3d 360 (2011).
E. Functional impact evidence
- Work restrictions and missed work documentation.
- Household limitations.
- Consistent reports of limitations to providers (not just to lawyers).
4) What if the defense argues your injury is from something else?
Defense causation attacks usually take one of these forms:
A. “This was preexisting.”
Nevada recognizes that prior injuries or preexisting conditions can be relevant to causation and damages, but Nevada appellate decisions also address limits on how that evidence is admitted and used.
A key Nevada Supreme Court decision explains that evidence of a prior injury or preexisting condition may be relevant in a personal injury action, but the defense generally must present competent evidence showing a causal connection between the prior condition and the current claimed injury. FGA, Inc. v. Giglio, 128 Nev. 271, 278 P.3d 490 (2012). The decision also discusses how expert testimony is often required on that causal-connection question unless the connection is readily apparent to a layperson. FGA, Inc. v. Giglio, 128 Nev. 271, 278 P.3d 490 (2012).
B. “Your symptoms don’t match the mechanism.”
This is where a well-documented mechanism explanation by a treating doctor can matter, including why the forces involved are consistent with the injury pattern.
C. “There were other causes after the accident.”
If multiple incidents contributed to injury (for example, a first accident and a second accident), Nevada law recognizes that apportionment issues can arise. In the successive-accident context, Nevada’s Supreme Court has discussed burden shifting once causation is established, placing pressure on defendants to apportion damages if they claim the harm is divisible. Kleitz v. Raskin, 103 Nev. 325, 738 P.2d 508 (1987).
5) Nevada evidence rules matter in causation fights
Causation disputes are not only medical, they are evidentiary. Nevada evidence statutes frame what can be presented to the jury.
Nevada defines relevant evidence broadly, admits relevant evidence unless excluded, and allows the court to exclude evidence if its probative value is substantially outweighed by dangers like unfair prejudice or confusion. NRS 48.015. NRS 48.025. NRS 48.035(1). FGA, Inc. v. Giglio, 128 Nev. 271, 278 P.3d 490 (2012).
Practically, those rules often show up in arguments about how much of your prior medical history the defense gets to present and whether it is being used fairly to address causation rather than to distract or prejudice.
6) Practical steps that help you prove causation
If you are still early in a claim, these steps tend to strengthen causation proof:
- Get evaluated promptly and be accurate about symptom onset and progression.
- Tell your provider about prior issues, but also clarify what changed after the accident.
- Follow through with recommended diagnostics, especially when symptoms persist.
- Ask your treating doctor to document causation clearly when appropriate, using probability-based language.
- Keep a simple timeline of symptoms, treatment, missed work, and functional limits.
Nevada Legal Authorities Cited
Statutes
- NRS 41.141
- NRS 48.015
- NRS 48.025
- NRS 48.035(1)
- NRS 51.115
Cases
- Taylor v. Silva, 96 Nev. 738, 615 P.2d 970 (1980).
- Mahan v. Hafen, 76 Nev. 220, 351 P.2d 617 (1960).
- Drummond v. Mid-West Growers Coop. Corp., 91 Nev. 698, 542 P.2d 198 (1975).
- Morsicato v. Sav-On Drug Stores, Inc., 121 Nev. 153, 111 P.3d 1112 (2005).
- Williams v. Eighth Judicial Dist. Court, 127 Nev. 518, 262 P.3d 360 (2011).
- FGA, Inc. v. Giglio, 128 Nev. 271, 278 P.3d 490 (2012).
- Kleitz v. Raskin, 103 Nev. 325, 738 P.2d 508 (1987).
If you need assistance with your personal injury case, don’t hesitate to contact Friedman Injury Law.
Friedman Injury Law
375 N. Stephanie St., Ste. 1411
Henderson, NV 89014
P: (702) 970-4222
W: blakefriedmanlaw.com