David Dao, the doctor who was unceremoniously dragged from a United Airlines flight last Sunday when he refused the airline's request to disembark the plane, filed a lawsuit against United late Wednesday.
Lawyers acting for the physician have filed an emergency request with an IL state court to require the airline to preserve video recordings and other evidence related to the incident.
As of Thursday, Dr Dao was reportedly still recovering from his injuries in a Chicago hospital.
"The overbooking process makes it possible to use seats on airplanes much more effectively", he said, arguing it helps the customer by allowing them to book on a sold-out flight that's unlikely to remain that way and the airline by helping ensure that all flights are at capacity.
In an interview with ABC's Good Morning America, United parent company chief executive Oscar Munoz said he felt "ashamed" watching video of the man being forced off the jet.
"That is not who our family at United is", he said.
The filing said "after being duly processed by the ticket agent, checked in by the attendant and seated in his assigned passenger seat, Petitioner was forcibly dragged and removed from the said aircraft by City employees, sustaining personal injury".
United shares have lost about 1 percent of their value since Monday.
Demetrio said his client accepts the apology.
The incident occurred when the airline was seeking to free up space on the plane for crew members it wanted to fly to Louisville.
The airline said it is "reaching out" to customers on Flight 3411 and "offering compensation for their flights".
Given the wide public outrage over the incident, Dao is in a strong position as he prepares to launch a legal action, lawyers who represent airlines and passengers said.
At a City Council committee hearing Thursday, aldermen ripped officials from United and the department about the episode.
Two online petitions calling for Munoz to step down as CEO had more than 124,000 signatures combined by Wednesday afternoon.
"United, if they're smart, will quickly and quietly settle the case".