Miller, 29, of Tustin was pronounced dead at the scene.
Newport Beach was well aware of the danger, Suk alleges in her claim, because eucalyptus trees previously fell nearby. Her claim also states that the city's construction on the median caused the tree's dangerous condition.
City Manager Dave Kiff told the Daily Pilot in November that the tree, which was near the Costa Mesa-Newport border but maintained by Newport, showed no visible signs of decay.
Public records have revealed that many of the other city-maintained blue gum eucalyptus trees are infected by sulfur fungus, which causes root rot and eventual collapse.
Newport Beach City Attorney Aaron Harp declined to comment. Costa Mesa's city spokesman Bill Lobdell and City Attorney Tom Duarte did not return calls for comment Friday.
Costa Mesa denied Chung's claim in a letter sent out Thursday and referred him to Newport Beach, citing an investigation by the city's Risk Management Division that concluded Newport Beach both maintained and controlled the tree.
"While we appreciate the inconvenience you have experienced, we are sure you can understand that the city cannot pay for damages for which it is not responsible," the letter states.
Suk alleges that Newport Beach tried to conceal evidence when it removed and destroyed about 100 eucalyptus trees from that stretch of Irvine Avenue soon after the accident. City officials there have declined to release the results of an investigation into the tree's collapse, citing pending litigation.
Chung's claim alleges both Costa Mesa and Newport were negligent in maintaining the tree.
Chung also alleges that emergency responders failed to stabilize the tree after it fell — a mistake that "caused or contributed" to Miller's death, it contends.
After the accident, witnesses said that firefighters began to lift the trunk when it dropped again on the car.
Chung is seeking to recover the cost of the car, punitive damages, emergency and medical bills, burial expenses, and "the loss of Ms. Miller's love, companionship … and guidance."
Suk lives in the High Desert near Palmdale and is represented by a Los Angeles law firm. Chung lives in South Korea and is represented by a Beverly Hills firm.