In the city of Port-au-Prince, Joseph Felix Badio was apprehended as he was leaving a grocery parking lot.
Colombian mercenaries killed Mr. Moise in his bedroom in 2021. Most have now either been killed or arrested.
His passing sparked a protracted political crisis in Haiti and resulted in levels of anarchy that were unheard before.
The capital's infrastructure and main petroleum port came under the grip of criminal gangs within a few months.
Mr. Badio is charged with giving the attack orders to hitmen. He is accused of committing armed robbery, murder, and attempted murder.
A few months prior to the assassination, according to local media, Mr. Badio had been removed from his position as a justice ministry anti-corruption official after he was allegedly paid to free a prisoner.
Following the murder, some of the hitmen were detained. They claimed that Mr. Badio, 60, had given them their orders.
The US has handed down convictions for other people connected to the case. Former senator from Haiti John Joel Joseph and businessman from Haiti and Chile Rodolphe Jaar are among them.
The proprietor of CTU Security in Florida, Venezuelan-American Antonio Intriago, has also been charged by the US with employing the hitmen. He is accused of several things, including plotting to assassinate or kidnap.
Since Mr. Moise's passing, Haiti's unelected administration has struggled to deliver even the most basic services.
This week, a UN report said that gangs had taken over much of the capital, operating hospitals and schools while terrorizing the populace and engaging in turf fights.
In Port-au-Prince, thousands of Haitians have fled their homes due to the intense violence, and many have already perished this year.
A recent UN resolution authorized the deployment of an international force to assist the Haitian police, but few nations have made manpower commitments, and the force has not yet arrived.
It accepted Kenya's proposal to command a multinational force to support order restoration earlier this month.