According to the 122-page document from Judge Walther Wesser Voltaire, made public by AyiboPost, the president's widow Martine Moise conspired with former Prime Minister Claude Joseph to kill the president in order to replace him herself.
Moise was shot dead when armed men broke into his Port-au-Prince bedroom on the night of July 7, 2021, a raid that left the former first lady injured.
The judge's order calls for the arrest and trial of those charged.
Haitian President Jovenel Moise with his wife Martine in 2017. (AP PHOTO)
The former first lady did not immediately respond to Reuters' request for comment, nor did Joseph. Moise has criticised on social media what she calls unjust arrests and political persecutions.
Joseph meanwhile told the Miami Herald the president's de-facto successor, Prime Minister Ariel Henry, was the main beneficiary and was now "weaponising the Haitian justice system" to persecute opponents in "a classic coup d'etat".
A spokesman for Henry's office said the judge was independent and "free to issue his order in accordance with the law and his conscience".
Henry was appointed to replace Joseph, who now leads an opposition party, days before the assassination. He pledged to hold elections but has postponed these indefinitely citing a devastating earthquake and the growing power of heavily-armed criminal gangs, for which he has sought foreign aid.
The gangs are now estimated to control most of the capital, and Kenya is preparing to lead a UN-ratified international force to support Haitian police, though prior abuses by foreign missions and allegations against Henry's government have left countries wary of volunteering support.
A separate case on Moise's killing is being tried in Miami, where six of 11 defendants have pleaded guilty to a plot to send Colombian mercenaries to kidnap Moise, a plan which was at the eleventh hour changed to a plot to murder him.
The conspirators had according to US charges sought to replace Moise with Haitian-American pastor Christian Emmanuel Sanon.
