Who Is at Fault in a Denver Bike Crash?

Fault is not automatic in either direction. Colorado gives a person on a bicycle the same rights and duties as the driver of any other vehicle, so fault comes down to who failed to obey the rules of the road, and Colorado law allows fault to be divided between both people.

The content on this page is provided for general informational purposes only and does not constitute legal advice. Reading this page does not create an attorney-client relationship. Laws vary by jurisdiction and change frequently. Always consult a licensed attorney for advice specific to your situation.

• A cyclist is not automatically the innocent party, and a driver is not automatically the responsible one.
• Colorado law treats a person on a bicycle as having the rights and duties of a driver.
• Fault can be split between both people by percentage.
• In Colorado, a person found to be 50 percent or more at fault recovers nothing.
• Physical evidence and independent witnesses usually decide these cases, not the two accounts given at the scene.

If you were hit while riding in Denver, call CGH Injury Lawyers at (720) 669-8062 to find out where you stand.

What does Colorado law actually say about cyclists?

The starting point is C.R.S. 42-4-1412(1), which states that a person riding a bicycle, electrically assisted bicycle, or electric scooter “has all of the rights and duties applicable to the driver of any other vehicle.”

That single sentence does most of the work. A cyclist has the right to be on the road and the obligation to obey signals, yield where required, and ride predictably, which is why a bicycle accident claim is argued on the same rules as any other crash.

Riders are also subject to local ordinances where cities have adopted them, so a Denver-specific rule can apply on top of the state code.

So how is fault decided?

The same way it is decided in any collision. Someone owed a duty of care, someone fell short of it, and that failure caused the crash.

A bicycle does not change that analysis, and Colorado’s rules for determining fault in car accidents apply in the same way. What changes is which specific rules were in play, because several traffic rules exist specifically to govern how vehicles and bicycles share space.

Which driver mistakes commonly create fault?

• Passing too closely. C.R.S. 42-4-1003(1)(b) requires a driver overtaking a bicyclist traveling the same direction to allow “at least a three-foot separation.” The statute measures the distance from the widest point of the vehicle and specifies that this includes all mirrors or other projections, so if a mirror does not clear the cyclist, then simply opening the door does not satisfy the rule.
• Turning right across a rider’s path is also a violation. A driver who passes a cyclist and then immediately turns right across them has cut off a road user who was lawfully proceeding straight.
• Turning left across an oncoming rider is another common hazard. Drivers frequently misjudge the speed of an approaching bicycle, and the duty to yield when turning left does not soften because the oncoming vehicle is a bike.
• Opening a door into traffic is also a violation. C.R.S. 42-4-1207 says no person shall open a vehicle door on the side available to moving traffic “unless and until it is reasonably safe to do so.” Violating it is a class B traffic infraction.
• Failing to look properly when pulling out. Bicycles are narrow and easy to miss in a glance, which is a reason to look twice rather than an excuse for not seeing one.

Which cyclist mistakes commonly create fault?

Because a cyclist carries a driver’s duties, a rider can be at fault for the same categories of error:

• Riding against traffic
• Running a red light or a stop sign
• Failing to yield when entering the roadway
• Riding unpredictably between lanes without signaling
• Riding at night without required lights or reflectors

A crash can also involve failures on both sides at once, which is where Colorado’s comparative fault rule takes over.

How does Colorado split fault between two people?

Colorado uses a modified comparative negligence rule at C.R.S. 13-21-111. Damages are reduced in proportion to the injured person’s own share of the negligence.

There is a hard cut-off. Under C.R.S. 13-21-111(3), if the injured person’s share is “equal to or greater than” the other party’s, the court enters judgment for the defendant and the injured person recovers nothing.

That threshold is 50 percent, not 51. A great deal of published material on Colorado law gets this wrong. The statute states that the threshold is equal to or greater than 50 percent, so an even split ends the claim.

Injured person’s share of fault	Effect on recovery
0 percent	Full damages
25 percent	Damages reduced by 25 percent
49 percent	Damages reduced by 49 percent
50 percent	Recovers nothing
51 percent or more	Recovers nothing

The practical consequence is that the argument over a few percentage points is not academic. Moving someone from 45 percent to 50 percent does not trim the claim. It ends it.

Were you the person on the bike? If you were hit while riding, the percentages above are the whole ballgame, and the other side’s insurer starts working on them immediately. Tell us what happened and we will tell you honestly where your case stands. No cost to talk. Call (720) 669-8062.

Why does the insurer’s version of events come first?

Adjusters often inflate the injured person’s share of fault to cut the payout, and the way they use your words against you is well documented. In bicycle cases they have a ready-made set of arguments, and they tend to reach for the same ones.

They will ask whether the rider was wearing a helmet. Colorado’s only bicycle helmet requirement sits at C.R.S. 42-4-1412(15)(b) and reaches just one narrow group, riders under eighteen on a class 3 electrically assisted bicycle. There is no general helmet requirement for adults on an ordinary bicycle.

The next subsection matters even more. C.R.S. 42-4-1412(15)(c) states that violating this helmet requirement “does not constitute negligence or negligence per se in the context of any civil personal injury claim or lawsuit seeking damages.” So even in the one situation where the rule applies, the legislature removed it as a fault argument.

They will ask whether the rider was visible, whether the bike had lights, and whether the rider was precisely where they should have been. Some of that is legitimate. Some of it is an attempt to build a percentage.

Answering those questions without preparation, before anyone has looked at the physical evidence, is how a rider ends up assigned a share of fault that the evidence does not support.

What evidence actually decides these cases?

The two accounts given at the roadside are rarely the deciding factor, because both people were frightened and neither saw the whole thing.

What tends to carry weight is more concrete:

• The point of impact on the vehicle and on the bicycle
• Where debris and the bicycle came to rest
• Nearby camera footage from businesses, homes, or traffic infrastructure
• Independent witnesses with no stake in the outcome
• Data from the vehicle, and from a rider’s cycling computer or phone
• The scene itself, including sight lines, lane width, and signage

Most of this information has a short shelf life. Footage is overwritten, vehicles are repaired, and the scene changes with the weather, which is why the steps you take right after a bicycle accident matter so much.

Does a traffic citation settle the question of fault?

It helps, but it does not end the matter. A citation is a police officer’s judgment about a traffic violation, and a civil fault determination is a separate question decided under a different standard.

A driver can be cited and still argue the cyclist contributed. A cyclist can be uncited and still be assigned a percentage.

The reverse also happens. Officers arrive after the fact, take a report under time pressure, and sometimes record an account that the physical evidence later contradicts. A citation issued to the rider does not end a claim, and neither does the driver’s absence of one.

What a citation does provide is a contemporaneous record of what an officer observed, and it is worth having and reading carefully.

Does it matter where the crash happened?

It can. A collision in a marked bike lane, at an intersection, in a crosswalk, or on a shared path each brings a slightly different set of rules into play.

Denver has also adopted local ordinances that apply on top of the state code, and C.R.S. 42-4-1412(1) expressly makes riders subject to them within incorporated cities and towns. Where the crash happened is therefore part of figuring out which rules applied at that moment.

How long do you have to bring a claim?

A bicycle crash involving a motor vehicle falls under the three-year deadline at C.R.S. 13-80-101(1)(n)(I), which covers all tort claims for bodily injury “arising out of the use or operation of a motor vehicle.” The rider does not lose the longer three-year period just because they are riding a bike.

If a public entity is involved, such as a collision with an RTD bus or a city vehicle, a written notice is also due within 182 days of discovering the injury under C.R.S. 24-10-109(1). That one is jurisdictional, and missing it bars the claim outright.

Frequently asked questions

Is the driver always at fault when a car hits a bicycle?

No. Colorado gives cyclists the rights and duties of a driver under C.R.S. 42-4-1412(1), so a rider who ran a red light or rode against traffic can be found at fault. Fault turns on conduct, not on which party was in the heavier vehicle.

Does not wearing a helmet make a cyclist at fault?

No. Colorado’s helmet rule at C.R.S. 42-4-1412(15)(b) applies only to riders under eighteen on a class 3 electrically assisted bicycle, and subsection (15)(c) states that violating it “does not constitute negligence or negligence per se” in a civil injury claim.

What is the three-foot rule in Colorado?

C.R.S. 42-4-1003(1)(b) requires a driver overtaking a bicyclist to leave at least three feet between the vehicle and the rider. The statute measures from the widest point of the vehicle, including mirrors and other projections, and it applies at all times during the pass.

Can fault be shared between the driver and the cyclist?

Yes. Under C.R.S. 13-21-111, a share of fault reduces damages proportionally, but if the injured person’s share is equal to or greater than the other party’s, they recover nothing. That cut-off sits at 50 percent.

What should a cyclist do at the scene?

Get medical attention, report the crash, and gather what will disappear quickly, including photographs and the contact details of any independent witness. Avoid giving a recorded statement to the other side’s insurer before getting advice.

Talk to a Denver lawyer who handles bicycle cases

Fault in a bike crash is decided on evidence that starts disappearing the same week. That is the practical reason these cases reward early attention.

If you were injured while riding in Denver or you lost someone in a crash and are facing a wrongful death claim, it costs nothing to find out where you stand.

Call CGH Injury Lawyers at (720) 669-8062. Tell us what happened, and se habla español.

Last updated: August 10, 2026

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