Does Lane Filtering Reduce Motorcycle Accidents?

Motorcycle safety remains a serious concern on American roads. Motorcyclists have far less physical protection than occupants of passenger vehicles, meaning that a crash that might result in minor property damage for a car driver can cause catastrophic or fatal injuries to a rider. According to the National Highway Traffic Safety Administration (NHTSA), 6,228 motorcyclists were killed in traffic crashes in 2024, accounting for 16% of all traffic fatalities. NHTSA has described this as one of the highest numbers of motorcyclist deaths since at least 1975.

One proposed way to reduce certain motorcycle accidents is lane filtering, a maneuver in which a motorcycle moves between lanes of stopped or slow-moving traffic, generally at a relatively low speed. Lane filtering is sometimes confused with lane splitting, but the terms can describe somewhat different riding practices depending on the jurisdiction. Lane splitting generally involves a motorcycle traveling between lanes of moving traffic, while lane filtering is typically associated with motorcycles moving between lanes of stopped or slow-moving vehicles.

Research from states where these practices have been permitted suggests that carefully regulated lane filtering or lane splitting may reduce some types of motorcycle crashes. However, the evidence does not mean that riding between lanes is automatically safe. Speed, traffic conditions, visibility, rider experience, and driver awareness can dramatically affect the risk.

For Illinois motorcyclists, there is another important consideration: whether the maneuver is legal under Illinois law. Illinois law requires vehicles on roadways with marked lanes to remain within a single lane as nearly as practicable and to make lane movements only after determining that the movement can be made safely. Illinois also places restrictions on how two-wheeled vehicles overtake other vehicles.

Why Motorcycle Crashes Are So Dangerous

Motorcyclists face a substantially greater risk of serious injury when involved in a collision. NHTSA reported that an estimated 82,564 motorcyclists were injured in crashes in 2023. The motorcycle fatality rate per 100 million vehicle miles traveled was 31.39, compared with 1.13 for passenger-car occupants, meaning the motorcycle fatality rate was nearly 28 times higher.

Motorcycle crashes are particularly dangerous because riders lack the occupant-protection systems found in passenger vehicles. A rider can be thrown from the motorcycle, struck by another vehicle, crushed between vehicles, or forced onto the pavement.

Common motorcycle accident injuries include:

• Traumatic brain injuries and concussions
• Spinal cord injuries and paralysis
• Broken arms and legs
• Road rash and severe skin injuries
• Internal bleeding and organ damage
• Facial fractures
• Amputations
• Shoulder and pelvic injuries
• Permanent disabilities
• Fatal injuries

NHTSA’s 2023 data also demonstrate the importance of protective equipment. Of the 6,335 motorcyclists killed that year, 3,949 were wearing helmets, while 2,162 were not wearing helmets among cases where helmet use was known or classified in the report. These statistics demonstrate why any traffic practice that could potentially reduce motorcycle collisions deserves careful examination.

What Is Lane Filtering?

Lane filtering generally occurs when a motorcycle travels between lanes of traffic while vehicles around the motorcycle are stopped or moving very slowly. The maneuver can allow a motorcycle to move toward the front of a traffic queue rather than remain directly behind a larger vehicle.

Lane filtering is different from simply changing lanes. Instead of moving completely into an adjacent lane, the motorcycle travels through the space between lanes.

Lane filtering is also different from traditional lane splitting, although the terms are sometimes used interchangeably in everyday conversation. Lane splitting generally refers to a motorcycle traveling between lanes while surrounding traffic is moving, whereas lane filtering is usually restricted to lower-speed traffic.

The distinction matters because speed differential, the difference between the motorcycle’s speed and the speed of surrounding vehicles, is an important factor in motorcycle crash risk.

What Does the Research Say About Lane Filtering and Crashes?

One of the most frequently cited studies concerning motorcycle lane splitting was conducted by researchers at the University of California, Berkeley’s Safe Transportation Research and Education Center. The researchers analyzed California motorcycle crash data and concluded that lane splitting appeared to be relatively safe when traffic was moving at 50 mph or less and the motorcycle was traveling no more than 15 mph faster than surrounding traffic.

The research produced several notable findings. Motorcycle riders who were lane splitting were injured less frequently in collisions than other motorcyclists in the study. Lane-splitting riders also experienced lower percentages of several types of injuries.

Among the findings cited in the California Department of Transportation’s review of the research:

• Head injuries occurred in approximately 9% of lane-splitting riders compared with 17% of other riders.
• Torso injuries occurred in approximately 19% compared with 29%.
• Extremity injuries occurred in approximately 60% compared with 66%.
• Fatal injuries occurred in approximately 1.2% of lane-splitting riders compared with 3.0% of other riders.

These numbers are significant, but they should not be interpreted as proof that lane filtering itself caused the lower injury rates. Researchers noted differences between lane-splitting and non-lane-splitting riders, including differences in traffic conditions, riding patterns, helmet use, alcohol consumption, and motorcycle speed.

In other words, the safest conclusion is not that lane filtering eliminates motorcycle crashes. Instead, carefully controlled lane filtering may reduce certain collision risks under specific conditions.

Why Could Lane Filtering Reduce Certain Motorcycle Crashes?

One potential advantage of lane filtering is that it can reduce a motorcycle’s exposure to rear-end collisions. Consider a motorcycle stopped at the back of a line of traffic. A distracted driver approaching from behind may fail to notice the motorcycle until it is too late. Because motorcycles are smaller than passenger vehicles, they can be more difficult for drivers to see, particularly at night, in congested traffic, or when a larger vehicle is nearby.

Lane filtering can potentially move a motorcycle away from that position and reduce the amount of time the rider spends directly behind stopped vehicles. Potential safety benefits may include:

• Reduced exposure to rear-end collisions.
• Less time spent sitting in congested traffic.
• Reduced exposure to vehicles approaching from behind.
• Potentially fewer motorcycle-versus-motor-vehicle conflicts in certain traffic conditions.
• Greater mobility through heavily congested traffic.

However, these potential benefits have to be weighed against the risks created when a motorcycle travels through a narrow space between vehicles.

Lane Filtering Can Also Create Serious Risks

Lane filtering is not inherently safe. A driver may suddenly change lanes without seeing the motorcycle. A passenger may open a door. A vehicle may drift across the lane line. A driver may become startled when a motorcycle approaches from an unexpected position.

The risk can become substantially greater when the motorcycle is traveling significantly faster than surrounding traffic.

The UC Berkeley research specifically found that the speed differential between a motorcycle and surrounding traffic was an important predictor of injury. The research found that speed differentials up to approximately 15 mph were not associated with increased injury occurrence, while greater differentials were associated with increased injury risk.

That finding provides an important lesson: lane filtering should not be viewed as permission to travel aggressively through traffic. A rider who travels slowly through stopped traffic is in a very different risk environment from a rider traveling 40 or 50 mph between lanes of vehicles traveling 10 mph.

What About Utah’s Lane Filtering Experience?

Utah provides another useful example because the state adopted a motorcycle lane-filtering law with restrictions. Utah’s highway safety data indicate that researchers and officials have attempted to monitor crashes involving lane filtering.

Utah’s annual highway safety report cautions that the available data remain relatively limited, making it difficult to determine the law’s overall effectiveness. Nevertheless, possible lane-filtering crashes decreased from 138 in 2021 to 106 in 2022, while possible lane-filtering fatalities declined from five to four. The report also noted that lane filtering was specifically identified in only 15 crash reports in 2022, demonstrating the difficulty of accurately tracking the maneuver in crash data.

This is important because crash statistics alone cannot always tell us whether a law caused crashes to increase or decrease. Researchers must account for rider behavior, traffic volume, roadway characteristics, weather, enforcement, motorcycle registrations, and other factors.

Does Lane Filtering Reduce Motorcycle Accidents?

The answer is potentially, but only under appropriate conditions and with reasonable restrictions.

The strongest available research does not establish that lane filtering universally reduces all motorcycle accidents. Instead, evidence suggests that carefully performed lane filtering in congested, low-speed traffic may reduce certain risks, particularly the risk of being struck from behind while sitting in traffic.

The California research is particularly relevant because it found lower injury rates among riders who were lane splitting under the conditions studied. At the same time, researchers emphasized that traffic speed and the motorcycle’s speed relative to surrounding vehicles were critical factors.

Therefore, whether lane filtering makes a rider safer depends on how, where, and when it is performed.

Illinois Motorcycle Riders Face an Important Legal Issue

Illinois motorcyclists should be particularly cautious before assuming that research from California or Utah automatically applies to Illinois. Illinois law requires vehicles traveling on roadways with multiple marked lanes to remain within a single lane as nearly as practicable and prohibits moving from a lane until the driver has determined that the movement can be made safely.

Illinois law also contains specific rules concerning overtaking and passing by two-wheeled vehicles. For example, the Illinois Vehicle Code restricts passing on the right unless an unobstructed lane of traffic is available to permit the maneuver safely.

Because the law can affect whether a particular maneuver is permissible, Illinois riders should not assume that a lane-filtering practice that is lawful in another state is automatically lawful in Illinois. After a collision, the legality of the motorcycle’s maneuver may also become relevant to questions of negligence and comparative fault.

Could Lane Filtering Affect an Illinois Motorcycle Accident Claim?

Yes. If a motorcycle accident occurs while a rider is filtering or attempting to pass between lanes, investigators may examine precisely what each person was doing immediately before the crash. Evidence may include:

• Traffic-camera footage
• Motorcycle or vehicle dash-camera recordings
• Witness statements
• Police crash reports
• Vehicle damage patterns
• Motorcycle damage
• Skid marks and roadway evidence
• Cellphone records
• Vehicle event-data information
• Photographs and video from the accident scene
• Medical records
• Accident reconstruction analysis

The fact that a motorcycle was between lanes does not automatically answer the question of who caused the collision. A driver who abruptly changes lanes without checking for a motorcycle, for example, may still have caused or contributed to the crash.

Conversely, evidence showing that a motorcyclist was traveling recklessly or violating traffic laws could become important in determining liability.

How Motorists Can Help Prevent Motorcycle Crashes

Lane filtering safety does not depend exclusively on motorcyclists. Drivers also have a responsibility to pay attention to motorcycles and check blind spots before changing lanes. Drivers should:

• Check mirrors and blind spots before changing lanes.
• Use turn signals early.
• Avoid sudden lane changes.
• Watch carefully for motorcycles in congested traffic.
• Maintain a safe following distance.
• Avoid distracted driving.
• Never assume a motorcycle is traveling slowly simply because it is small.
• Give motorcycles adequate space.

Motorcyclists should likewise ride defensively, maintain appropriate speeds, use headlights and conspicuous gear, avoid riding impaired, and maintain an escape route whenever possible.

Frequently Asked Questions About Lane Filtering

Is lane filtering safer than remaining behind stopped traffic?

It can be under certain circumstances. Research indicates that carefully performed lane splitting or filtering in low-speed traffic may reduce certain collision and injury risks, including exposure to rear-end crashes. However, lane filtering can create other risks, particularly when the motorcycle travels too quickly relative to surrounding vehicles.

Does lane filtering prevent motorcycle accidents?

No. Lane filtering cannot eliminate motorcycle accidents. It may reduce certain types of crashes under controlled conditions, but it can also create collision risks if performed aggressively or in inappropriate traffic conditions.

What is the safest speed for lane filtering?

There is no universal speed that makes lane filtering safe in every situation. The California research found relatively favorable safety outcomes when surrounding traffic was traveling at 50 mph or less and the motorcycle was not traveling more than 15 mph faster than surrounding traffic.

Is lane filtering legal in Illinois?

No. Illinois law contains restrictions governing lane use and overtaking by two-wheeled vehicles.

Who is responsible if a driver hits a motorcycle while it is lane filtering?

Liability depends on the facts. Investigators may consider whether the driver changed lanes without checking, whether the motorcycle was traveling at an unsafe speed, whether either party violated traffic laws, and what other evidence establishes about the collision.

What should I do after a motorcycle accident?

Seek medical attention, report the collision, document the scene if you are able, obtain witness information, preserve photographs and video, and avoid making statements accepting blame before the circumstances have been fully investigated. If you suffered significant injuries, consider speaking with an experienced motorcycle accident attorney.

Contact the 5-Star Rated Illinois Motorcycle Accident Lawyers at John J. Malm & Associates

The evidence suggests that properly controlled lane filtering or lane splitting may reduce certain motorcycle crash and injury risks, particularly in congested, low-speed traffic.  But motorcycle riders remain highly vulnerable on American roads. Whether a motorcycle was filtering, splitting lanes, changing lanes, or traveling normally, the circumstances of a collision deserve careful investigation.

If you or someone you love has been seriously injured in a motorcycle accident in Illinois, the top-rated motorcycle accident attorneys at John J. Malm & Associates can investigate the crash, identify the responsible parties, gather critical evidence, and pursue the compensation you may be entitled to receive. Our attorneys understand the unique dangers motorcyclists face and the ways insurance companies may attempt to blame riders for their own injuries. Contact John J. Malm & Associates today for a free consultation about your motorcycle accident and your legal options.