If you’ve driven through downtown San Antonio on I-35, you already know the problem: the upper/lower deck splitforces fast decisions in heavy traffic, often with short merge distances and limited room to recover if you pick the wrong lane. That “decision pressure” is exactly why this corridor is a hotspot for last-second lane changes, abrupt braking, and sideswipe collisions—especially when there are lane shifts or closures related to ongoing repairs in the downtown I-35/I-10 area.
The key legal question after one of these crashes is usually the same:
If the split is confusing, does that change who is at fault in Texas?
Quick Answer
- Most I-35 upper/lower split wrecks come down to driver conduct, not the roadway itself—especially unsafe lane changes, failure to stay in a lane until it’s safe to move, and following too closely.
- “I was confused” rarely excuses a collision. In Texas, the issue is typically who created the hazard (for example, a last-second cut across lanes or a sudden stop in a travel lane).
- Texas proportionate responsibility matters: if you’re found more than 50% responsible, you generally cannot recover damages.
- Deadlines are real: most injury lawsuits must be filed within two years of when the claim accrues.
- If a governmental entity could be involved (signage/road condition issues), the Texas Tort Claims Act has notice requirements that can be as short as six months, and some cities have charter-based notice provisions.
Why the I-35 Upper/Lower Split Produces So Many “Panic” Crashes
The upper/lower split is a classic “commitment zone.” Drivers realize late that they’re on the wrong deck, then try to fix it quickly—often while boxed in by traffic. The most common crash patterns we see around these downtown decision points are:
- Sideswipes from sudden lane changes across solid lines or short gaps
- Rear-end collisions after abrupt braking (often a chain reaction)
- Merge/yield disputes where a driver forces entry instead of waiting for a safe opening
Downtown traffic conditions can also change quickly during construction or repair work. TxDOT’s downtown I-35/I-10 repairs are a multi-phase effort along key downtown segments, and TxDOT specifically directs drivers to check DriveTexas for current closures/conditions.
The Texas Rules That Most Often Decide Liability at the Split
Insurers and juries don’t decide fault based on who had the best reason to move lanes. They decide based on whether the move was legally safe and reasonable under the circumstances.
Here are three Texas concepts that frequently determine liability in upper/lower split collisions:
1) Unsafe lane movement (the “stay in your lane unless it’s safe” rule)
Texas law requires a driver to stay within a lane as nearly as practical and not move from the lane unless the movement can be made safely.
How it applies at the split:
If a driver cuts across late because they picked the wrong deck, that driver is often blamed for creating the hazard—especially in sideswipe cases.
2) Following distance (rear-end and chain reaction cases)
Texas law also requires maintaining an assured clear distance so you can stop safely without hitting the vehicle ahead.
How it applies at the split:
Rear-end claims often start with a presumption that the trailing driver was following too closely, but the facts can shift if the lead driver made an unreasonable stop in a travel lane to avoid missing the split.
3) Turn signals and lane-change signaling
Drivers must use signals to indicate an intention to turn or change lanes.
How it applies at the split:
When liability is disputed (“They came out of nowhere”), signaling evidence—especially dashcam footage—can be meaningful.
Common Crash Scenarios at the Upper/Lower Split (and How Fault Is Typically Argued)
Scenario A: The last-second “dive” across lanes (sideswipe)
Typical liability theory: unsafe lane change / failure to move safely.
What the other side will claim: “They sped up,” “They were in my blind spot,” “They wouldn’t let me in.”
Evidence that usually decides it: dashcam video, independent witnesses, and damage angles (which panel hit which).
Scenario B: Sudden braking to avoid missing the deck or exit (rear-end or chain reaction)
Typical liability theory: following too closely (for the rear driver).
But the nuance: if the front driver stopped abruptly in a travel lane for a non-emergency reason, insurers often argue comparative fault.
Scenario C: Merge/yield conflict at a connector
Typical liability theory: the entering/merging driver forced entry without a safe opening.
Common defense: “Traffic forced me” or “They blocked me.”
Liability Cheat Sheet Table: What Adjusters Look For Downtown
| Crash pattern at the I-35 upper/lower split | What insurers focus on | Best evidence to preserve | How liability often gets spun against you |
|---|---|---|---|
| Sideswipe from a late lane change | Was the lane move safe? | Dashcam, witness info, photos of lane markings/signage | “You didn’t leave room / you sped up” |
| Rear-end after abrupt braking | Assured clear distance | Dashcam, scene photos, sequencing of impacts | “You stopped for no reason” (against the lead driver) |
| Chain-reaction pileup | Who initiated the first impact | Multi-car dashcams, witness statements, crash report diagram | “I was pushed into them” |
| Merge conflict onto a connector | Yield/safe entry, predictability | Wide-angle photos, video showing gap timing | “They blocked me from merging” |
| Confusion due to traffic shifts/closures | Road condition context (not a defense by itself) | Photos of signs, barrels, lane shifts; DriveTexas screenshots (when safe) | “You should have driven slower / taken the next exit” |
Texas Proportionate Responsibility: Why the “51% Rule” Is a Big Deal Here
Downtown split cases are notorious for insurers pushing shared fault because both drivers are often moving, braking, and merging at the same time.
Under Texas proportionate responsibility, a claimant generally cannot recover damages if their percentage of responsibility is greater than 50%.
That’s why evidence matters. A “50/50” insurance decision can be the difference between progress and a stalemate.
What If Poor Signage or Road Conditions Contributed?
People understandably ask: Can I sue TxDOT or the City because the split is confusing?
Sometimes—but those claims are constrained by statute.
- The Texas Tort Claims Act includes a notice requirement: a governmental unit is entitled to notice not later than six months after the incident, and city charter provisions can impose their own notice deadlines.
- The Act also contains significant limitations and exceptions, including provisions addressing traffic/road control devices (and when a governmental unit can be liable for absence/condition/malfunction after notice).
Practical takeaway: If you suspect a roadway condition, missing sign, or construction-related traffic shift played a role, you should preserve location-specific proof early. The downtown corridor is actively maintained and can change over time.
What To Do After a Crash at the I-35 Split (Claim-Protecting Checklist)
At the scene (if safe)
- Call 911 and request medical help if anyone is injured.
- Photograph:
- Vehicle positions (wide + close)
- The exact deck/connector you were on (upper vs. lower)
- Lane markings, gore areas, barriers, skid marks
- Any construction signs, lane-shift indicators, or closures (do this only when safe)
Within 24–72 hours
- Get medical evaluation if you have headache, dizziness, neck/back pain, numbness, or delayed symptoms.
- Preserve evidence:
- Save dashcam footage immediately (many systems overwrite quickly)
- Write down what you remember: deck level, lane, traffic density, lighting, weather
- Obtain the crash report when available (commonly the CR-3). TxDOT provides a crash report portal and guidance on crash records.
Insurance Basics That Matter in These Cases (Plain English)
Your case value and options often depend on the coverage available:
- Liability coverage: the at-fault driver’s policy may pay up to its limits.
- PIP/MedPay and UM/UIM: these are optional coverages that can provide additional paths depending on what was purchased; the Texas Department of Insurance explains common auto coverages, limits, and deductibles.
How Long Do I Have to File in Texas?
Most personal injury lawsuits must be brought within two years after the claim accrues.
Waiting can hurt even before a deadline because video disappears, witnesses move, and the roadway configuration may change.
Attorney Insight: The “Confusing Highway” Argument Can Be a Trap
In practice, the strongest cases don’t argue, “The split made me do it.” They show:
- You drove predictably and stayed committed to a safe lane plan, and
- The other driver created the hazard with an unsafe move—late cross-lane dive, forced merge, or abrupt stop.
That framing aligns with how liability is usually evaluated under Texas rules about lane movement and safe distance.
FAQs (Short, Snippet-Friendly Answers)
Can I still recover if I was partly at fault at the I-35 split?
Possibly. Texas reduces recovery by your percentage of responsibility, but you generally cannot recover if you’re more than 50% responsible.
What if the other driver says I “wouldn’t let them merge”?
That’s common here. The deciding proof is usually video, damage angles, and whether the merging driver had a safe opening before forcing entry.
Does not using a turn signal matter?
It can. Signaling is part of showing a lane change was made responsibly, and it often becomes important when stories conflict.
How do I get the police crash report in Texas?
TxDOT provides a crash report purchase portal and a crash-records page explaining access.
What if I think a roadway condition or signage issue contributed?
Governmental claims can involve strict notice rules, including a six-month notice provision under the Texas Tort Claims Act (and potentially shorter city charter deadlines).
Ryan Orsatti Law
4634 De Zavala Rd, San Antonio, TX 78249
Phone: 210-525-1200
“This blog is for informational purposes only, not legal advice. Reading it does not create an attorney-client relationship. Past results do not guarantee future results.”