this excerpt is from the U. S. Supreme Court decision in Brown v. Board of Education of Topeka, Kansas (1954). in the excerpt from the Court's ruling, what does the word "instrument" mean?

Ayne adair, a california resident, fell from the third tier of seats at wrigley field while she was attending a jimmy buffett concert held there to raise money for the victims of hurricane katrina in september 2005. she experienced paralyzing injuries and has hospital bills of $100,000 and the bills from her stay at the rehabilitation center total $76,000 so far. jayne feels that the railing on the third tier was weak and collapsed when she leaned on it. she wants to bring suit against the chicago cubs, the managers of wrigley field, and jimmy buffett and his manager. the cubs have their business offices in chicago, wrigley field is managed by a chicago company, and jimmy buffett lives in margaritaville, off-shore from the united states. which court would have jurisdiction over jayne's case? that is, where does she need to file her suit?