King County, WA — March 2, 2025, Siham Hassan was killed following a car accident that occurred at around 12:30 A.M. on Interstate 5.

An investigation is underway following an car accident that left one person dead during the early-morning hours of March 2nd. According to official reports, Siham Hassan was travelling in a Mercedes GLS on I-5 in the northbound lanes, when for unknown reasons the Mercedes struck another vehicle, causing the GLS to roll several times.

When first responders arrived on the scene, they found that Hassan had sustained fatal injuries and she was pronounced deceased. At this time there has been no further information released from the accident, including the status of Hassan's injuries, however this remains an ongoing investigation and more details may be released by authorities in the future.

Commentary by Attorney Michael Grossman

When I read about a crash like this, my first thought is that I hope investigators can provide clear answers for the loved ones of those involved. A high-speed collision on the interstate that results in a vehicle rolling multiple times raises serious concerns about road conditions, possible mechanical failures, and whether external factors played a role. While initial reports confirm what happened, they don’t necessarily explain why it happened. To truly understand the cause, three critical questions must be asked.

First, have authorities thoroughly investigated the crash? Law enforcement will typically document the scene, assess road conditions, and consider possible contributing factors such as weather, visibility, and roadway hazards. However, deeper analysis is often necessary. Were there environmental conditions—such as wet pavement, low visibility, or debris—that may have played a role? Were there signs that the other vehicle involved made an abrupt or unexpected maneuver? A full accident reconstruction could help determine whether external conditions contributed to the crash.

Second, has anyone looked into the possibility of a vehicle defect? When a vehicle rolls multiple times after a collision, it’s important to consider whether mechanical failures—such as brake malfunctions, steering issues, or stability control failures—may have played a role. Additionally, luxury SUVs like the Mercedes GLS have advanced safety systems—did those systems function properly in an attempt to prevent the crash or minimize the severity of the rollover? If a defect is suspected, ensuring that all relevant mechanical and electronic data is reviewed is critical before key evidence is lost.

Third, has all electronic data relating to the crash been collected? The vehicle’s electronic control module (ECM) may provide key insights, including speed, braking attempts, and steering input leading up to the crash. Additionally, traffic cameras, dashcams from other vehicles, or nearby surveillance footage may offer valuable information about the moments leading up to the impact. If investigators don’t secure this evidence quickly, it may be lost, making it much harder to determine exactly what led to the crash.

At the end of the day, the victim’s family deserves clear answers. If the official investigation leaves any gaps, independent experts may be needed to ensure that every possible factor is considered. Whether the cause was environmental, mechanical, or something else entirely, the community owes it to those affected to make sure all available evidence is carefully examined.