Aguer was arrested last year after he and other activists co-founded a civic group known as the People’s Coalition for Civil Action (PCCA).
Addressing reporters in Juba outside a courtroom shortly after his release Friday, the former state governor said the team of judges who presided over his case have displayed he called "national integrity."
"I would like to thank the judiciary of South Sudan for exercising the power of law and power of the constitution," he said. "I am sure I have not committed any crime against my country. South Sudan is a country I love, I struggled for, and I will die for. Therefore, I cannot do anything that will harm."
Aguer was arrested in August 2021 and charged under several articles of the South Sudan penal code.
The former governor was then detained in Juba at the National Security Service detention facility known as "Blue House" for more than a year before he was summoned to a special court in October this year.
Kiir Chol, one of Aguer’s defense lawyers, says the dismissal is a victory for freedom of speech in South Sudan, adding "the decision has served justice not only for Kuel Aguer but to the nation and the citizens of South Sudan who would wish to criticize their government."
Chol says freedom of expression and opinion are enshrined under Article 25 of South Sudan’s constitution as well as Article 24, which protects the rights of citizens to criticize the government.
Aguer says all the accusations leveled against him were false and promised to continue with his fight for freedom in South Sudan.
"I shall continue to call for democracy, I shall continue to call for freedom and I shall continue to call for justice and equality in this country. We liberated South Sudan so that we have a country of which each and every citizen is a first class citizen. Nobody is a second class citizen. And nobody is a follower of anybody. We are all free. We are not anybody's property," Aguer said.
Latjor Kueth Jal, head of the prosecution team, says his side did their best to present a strong case against Aguer. He says the prosecution may appeal.
"The court dismissed the charges against the accused and released the accused immediately. So as the prosecution, we presented what we presented to the court. The court has a right to evaluate evidence presented to it. So it is a decision, and we have a right to appeal that decision within fifteen days from today," he said.
Seven other PCCA activists accused of calling for a mass protest in 2021 were tried in absentia in October this year after they fled the country for safety.
In August and September, PCCA’s calls for peaceful protests were met with a government crackdown.
Security forces were deployed to the streets of Juba where they detained civil society activists and shut down a radio station in Jonglei State and the Sudd institute, an academic think-tank which resumed operations in September.