Wal-Mart Stores has spent a year and more than a million dollars in legal fees battling a $7,000 fine that federal safety officials assessed after shoppers trampled a Wal-Mart employee to death at a store on Long Island on the day after Thanksgiving in 2008.

The mystery, federal officials say, is why Wal-Mart is fighting so hard against such a modest fine.

It is not as if Wal-Mart has not already taken action to address any missteps and prevent another such accident. Three weeks before the federal Occupational Safety and Health Administration ordered the fine, Wal-Mart, seeking to avoid criminal charges, reached a settlement with the Nassau County, N.Y., district attorney that called for the company to adopt new crowd management techniques in all 92 of its stores in New York State. At the time, Wal-Mart also agreed to create a $400,000 fund for customers injured in the stampede and to donate $1.5 million to various community programs in Nassau County.

More recently, the company announced improved crowd-control policies for all its United States stores to try to prevent such an accident from happening again.

But in fighting the federal fine, Wal-Mart is arguing that the government is improperly trying to define “crowd trampling” as an occupational hazard that retailers must take action to prevent.