Christopher Kortlander, owner of the Custer Battlefield Museum, is suing federal Bureau of Land Management agents, claiming they violated his rights when they searched his business five years ago.
Kortlander alleges in a complaint that there was no probable cause to execute a search warrant on the museum, located in Garryowen, and that the warrant was flawed and misleading.
He also alleges that the agents tried to entrap him into committing a crime.
The suit names Brian Cornell, a BLM special agent; Bart Fitzgerald, a BLM special agent in charge at the time of the search; Doug Goessman, a U.S. Fish and Wildlife Service special agent, and 21 or more unnamed federal agents.
Kortlander filed the suit Monday in U.S. District Court in Billings.
The suit stems from a search of the museum by federal agents in March 2005.
At the time, the BLM said it was looking into issues involving artifacts. Another search was conducted in November 2008.
Agents seized items, but no charges were filed against Kortlander and the case was closed.
Kortlander alleges the searches violated numerous rights, including his right to due process and to be safe from unreasonable searches.
In October, Kortlander sued the BLM to force it to give him documents related to the investigations and searches of his businesses.