Ex-Fugees musician Prakazrel “Pras” Michel has been found guilty of 10 counts, including corruption, stemming from allegations he used money to peddle influence in the US.
US prosecutors said Michel had received more than $100m (£80m) from Malaysian billionaire Jho Low that was used in two efforts to influence US politics.
The self-identifying “celebrity surrogate” was also convicted of lobbying on behalf of China’s government.
The rapper now faces years in prison.
Michel, 50, was convicted in a Washington DC court of campaign finance violations, acting as an unregistered foreign agent, witness tampering and lying to banks.
His lawyer, David Kenner, said that he was disappointed with the outcome of the trial and planned to file an appeal.
“This is not over,” Mr Kenner said. “I remain very, very confident that we will ultimately prevail in this matter.”
Mr Kenner said he had also filed motions for a mistrial.
The trial, which began on 30 March, saw testimony from Hollywood star Leonardo DiCaprio, as well as former US Attorney General Jeff Sessions.
The Grammy-winning musician was accused of bringing “secret, illegal, foreign influence to bear” during the administrations of Barack Obama and Donald Trump, between 2012 and 2017.
Businessman Mr Low, who funnelled money to Michel, is accused of stealing about $4bn from Malaysia’s sovereign wealth fund during the infamous 1MDB scandal.
Mr Low, who is currently wanted by the US government, allegedly helped finance DiCaprio’s 2013 film The Wolf of Wall Street with money stolen from the sovereign fund.
Michel was alleged to have helped lobby Trump-administration officials to abandon their investigation into Mr Low’s part in it.
A file photo of Lauryn Hill and her two band members Wyclef Jean (C) and Pras Michel (R) of the US group Fugees perform on stage on Tuesday, 06 December 2005. EPA/Patrick Lux