President Jovenel Moïse of Haiti was about to name names.

Before being assassinated in July, he had been working on a list of powerful politicians and businesspeople involved in Haiti’s drug trade, with the intention of handing over the dossier to the U.S. government, according to four senior Haitian advisers and officials tasked with drafting the document.

The president had ordered the officials to spare no one, not even the power brokers who had helped propel him into office, they said — one of several moves against suspected drug traffickers that could explain a motive for the assassination.