Holding an oil company liable for purported environmental damage isn’t a typical assignment for an Am Law 100 firm. But when an unusual bankruptcy proceeding offered Kirkland & Ellis the opportunity to do just that, a trial team led by David Zott left no stone unturned—seeking out evidence from Wall Street to the Navajo Nation—and delivered what may go down as the biggest judgment of the year.

Siding with a litigation trust represented by Zott, U.S. Bankruptcy Judge Allan Gropper in Manhattan ruled on Dec. 12 that Kerr-McGee Corporation’s spin-off of Tronox Ltd. was a fraudulent transfer intended to shield billions of dollars in assets from the U.S. Environmental Protection Agency, a dozen states, the Navajo Nation and other municipalities and individuals holding pollution-related claims. While Gropper hasn’t yet awarded damages, he indicated that he will put Kerr-McGee’s parent, Anadarko Petroleum Corporation, on the hook for between $5 billion and $14 billion. (Read our previous coverage here.) Anadarko can appeal, but some analysts predict a settlement is in the works.