Lawyer Jordan Hecht said Monday that Jdimytai Damour had been working at the Long Island store for only about a week when frenzied shoppers knocked him down on the day after the Thanksgiving holiday, which is known for its huge sales.
Nassau County Police Commissioner Lawrence Mulvey says a preliminary investigation shows Wal-Mart failed to provide adequate security outside the store.
Wal-Mart did not immediately respond to a request for comment. It has said security precautions were in place.
Nassau County police say an autopsy found Damour died of asphyxiation related to his trampling.
Police were reviewing video from surveillance cameras in an attempt to identify who trampled to death Damour.
Criminal charges were possible, but identifying individual shoppers in Friday's video may prove difficult, said Detective Lt. Michael Fleming, a Nassau County police spokesman.
Other workers were trampled as they tried to rescue the man, and customers stepped over him and became irate when officials said the store was closing because of the death, police and witnesses said.
At least four other people, including a woman who was eight months pregnant, were taken to hospitals for observation or minor injuries. The store in Valley Stream on Long Island closed for several hours before reopening.
Police said about 2,000 people were gathered outside the Wal-Mart doors before its 5 a.m. opening at a mall about 20 miles east of Manhattan. The impatient crowd knocked the employee, identified by police as Jdimytai Damour, to the ground as he opened the doors, leaving a metal portion of the frame crumpled like an accordion.
"This crowd was out of control," Fleming said. He described the scene as "utter chaos," and said the store didn't have enough security.