Traffic Collision Reconstructionist Expert Testifies for the Defense


by Nabil Sirur

SAN FRANCISCO – The case against Willie Flannigan has continued on its third week with an important figure on the witness stand. In this case, the District Attorney is attempting to convict Flannigan on charges which include felony hit and run on an officer and evading a peace officer among other charges.

The facts are that Mr. Flannigan was coming out of a plaza exit garage and made a left to enter into a one-way street named Turk St. On his left side, there was a budget truck parked up which was crucial for the defense. As soon as he made a left turn, he collided with Officer Elia Lewin-Tankel who was on a police bike.

There was a camera available across the street from where the exit occurred and it shows that there was a budget truck right next to the exit. The defense argues that when Mr. Flannigan came out of the exit garage, it was impossible to even see the officer on the bike due to the budget truck being there to obstruct his vision.

The important figure on the witness stand was Mr. Kauderer, a traffic accident reconstructionist expert for 34 years. He surprised the courtroom by willing to testify on the stand for the defendant. His occupation also includes being an instructor and teaching all around the nation on matters pertaining to traffic accident collision and mechanical engineering.

Throughout his career, he has testified roughly 150 times in court regarding accident collisions and has been of assistance with criminal as well as civil matters.

Initially, the District Attorney had contacted Mr. Kauderer first to testify on the prosecution’s behalf. Mr. Kauderer has reviewed all the materials pertaining to the collision between the SUV Lexus, which Mr. Flannigan drove and Elia Tankel’s police bike. He identified and analyzed the damages to the car as well as finding hair from Elia Tankel’s body on the left front corner of the vehicle indicating a collision.

When he was finished with his analysis between the SUV and the officer, he came to the conclusion that Mr. Flannigan could not have possibly seen and known the officer’s presence on the bike because of the budget truck being in the way. The street Mr. Flannigan entered was a one-way street while the officer was coming the wrong way.

The formula as to how he came to that conclusion was a combination of the video camera analysis across the street from the exit as well as visibility analysis of Mr. Flannigan seeing the road on his left side after coming out of the exit. He also analyzed the perception response time procedure which deals with seeing an object, perceiving that object and deciding what to do.

Mr. Kauderer testified that it takes the average driver 1 to 1.4 seconds to go through the perception response time procedure. According to the expert, Mr. Willie Flannigan had only 8/10ths of a second to react which is nearly impossible to decide instantly what to do.

The traffic accident reconstructionist expert agreed with the defense counsel that Mr. Flannigan did not have enough time to shift or maneuver his car because the budget truck created a visual obstruction for the defendant.

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About The Author

David Greenwald is the founder, editor, and executive director of the Davis Vanguard. He founded the Vanguard in 2006. David Greenwald moved to Davis in 1996 to attend Graduate School at UC Davis in Political Science. He lives in South Davis with his wife Cecilia Escamilla Greenwald and three children.

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One thought on “Traffic Collision Reconstructionist Expert Testifies for the Defense”

  1. Darell Dickey

    The article’s title is great! Yet…

    >> a traffic accident deconstructionist expert <<
    If this is his self-proclaimed title, I suppose we have to suffer through the fact that he deconstructs collisions while referring to them all as accidents even before negligence is determined.

    >> matters pertaining to traffic accident collision … regarding accident collisions…<<
    But this is pure absurdity. An accident collision? Everything he looks at are collisions. If they’re perhaps also “accidents” is what he is supposedly determining… while his title presupposes that everything he deconstructs are all accidents to begin with.

    I guess I’ll never figure out this insistence on calling EVERYTHING that goes bump on the road an “accident.” Even while we try diligently to determine negligence and cause.

    We here in the Intentional Killing Department investigate all killings that are intentional, to determine if they are intentional.

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