The bribery and fraud conviction of a former close aide and confidant to ex-Gov. Andrew Cuomo was tossed by the U.S. Supreme Court on Thursday in a decision upending a milestone corruption case.

The court's decision also overturned the conviction of Alain Kaloyeros, the former top official of SUNY Polytechnic who was convicted as well in a sweeping bribery and fraud case. 

The unanimous ruling by the court centered around the bribery conviction of Joe Percoco, a former longtime advisor to Cuomo who was charged in 2016 in a wide-ranging bribery and bid rigging case that also drew in prominent upstate developers as well as Kaloyeros.

Percoco, who was convicted in 2018, had long served as a prominent advisor to Cuomo both in government and on his political campaigns.

The court determined Percoco's case should be tossed based on faulty instructions given to the jury at the time given his role as a top campaign official for Cuomo's re-election in 2014, a key time period in the case.

Justice Samuel Alito wrote in the ruling the jury had to determine whether Percoco had a "'special relationship' with the government and had 'dominated and controlled' government business" as a result of his status.

"We conclude that this is not the proper test for determining whether a private person may be convicted of honest-services fraud, and we therefore reverse and remand for further proceedings," Alito wrote.

Percoco's conviction capped an era in state government in which prominent New York officials were charged and convicted in blockbuster corruption cases. Those cases included the conviction of former Assembly Speaker Sheldon Silver and ex-Senate Majority Leader Dean Skelos.

The public corruption cases were brought by then-U.S. Attorney Preet Bharara in the Southern District of New York.

Percoco's case was overturned alongside that of Louis Ciminelli, who was also convicted in a linked case that grew out of a federal investigation of the Buffalo Billion economic development program.

Developers Joe Girardi and Steven Aiello are also seeking to have their cases appealed.