Mahdavi Far was summoned and interrogated by Branch 2 of the interrogation service in Aran-o-Bidgol, on behalf of the Kashan branch, in 2014, after writing a 32-verse poem called Alefba ("Alphabet") and reciting it in literary gatherings in Kashan.

He was tried for "spreading lies" in Kashan Branch 105 and was sentenced to 1.5 years in prison.

The sentence was handed down to Branch 23 of the Isfahan Court of Appeals, headed by Hamid Reza Amani, on July 2, 2016. The charge was changed to "propaganda against the regime" and the sentence was changed to ten months in prison; and then in accordance with Article 3, Parb B of the sentencing or punishment laws, it was reduced to a fine of three million tomans.

Mahdavi Far was arrested again by intelligence agents on September 19, 2016, at his home. He was released on November 2, 2016, after 45 days in solitary confinement in the Intelligence Ward of Isfahan Prison.

At the time, a relative of Mahdavi Far told HRANA that in the days before his arrest, his Telegram channel had been hacked by the Revolutionary Guards.

He was arrested again on May 27, 2017.

Mahdavi Far was then accused of "insulting the Supreme Leader," "insulting the founder of the Islamic Republic," "insulting Imams," "acting against national security through contact with hostile states [and] contact with anti-revolutionary elements via traveling to the cities of Tehran, Yazd, Kerman and else."

The hearing was held in the Revolutionary Court in the fall of 2017. The verdict sentenced Mahdavi Far to a total of three years in prison and four years in exile in Sarbaz on the charge of "insulting the Supreme Leader" and "insulating the founder of the Islamic Republic." The court acquitted Mahdavi Far of the other charges. He was released on bail in November 2017.

Branch 18 of the Isfahan Court of Appeals later overturned the supplementary sentence of exile and sentenced Mahdavi Far to two years in prison.

Mahdavi Far, who had increased his Telegram activities in the midst of the nationwide protests in Iran in January 2018, was arrested on January 14, 2018, and while living in Mashhad, he was transferred to Isfahan Central Prison to serve his two years sentence.

About two months after the start of his sentence, Branch 102 of the Aran-o-Bidgol Criminal Courts, for another part of the case, sentenced Mahdavi Far to two years in prison in March 2018 on charges of "publishing lies with the intention of disturbing public opinion" and fined him four million tomans. The verdict was confirmed in Branch 16 of the Court of Appeals of Isfahan province in June 2018.

On July 3, 2018, Saeed Gholamian, Mahdavi Far's lawyer, told Hrana regarding his client’s case: "In a case with multiple punishments, the sentence that is the most severe is enforced. This case has two sentences and usually and commonly the sentence of two-year imprisonment and the four million toman fine should have been what was enforced.”

Hrana meanwhile reported that Mahdavi Far, who had respiratory problems due to exposure to chemical weapons during the Iran-Iraq war, was being held in a public ward next to drug addicted prisoners, without any regards to the principle of separating prisoners based on their crime.

Once the verdict of the second case was issued, another case was opened against him in July 2018 in Branch 101 of the Aran-o-Bidgol Criminal Court, presided over by Judge Arshadi.

Mahdavi Far was charged in the criminal court with "insulting the Supreme Leader of the Islamic Republic" and "spreading lies online with the intention of disturbing public opinion." Mahdavi Far was tried on July 8, and Branch 101 of the Criminal Court sentenced him to eight months in prison on charges of spreading lies.

For the second part of the case, the charges of "insulting the Supreme Leader" and "propaganda against the regime" were reviewed in Branch 1 of the Revolutionary Court on September 2, and he was sentenced to 4.5 years in prison and four years in exile in Sarbaz.

Mohammad Najafi, Mahdavi Far's lawyer, announced on October 1, 2018, that his client had been sentenced to imprisonment and exile. He wrote: "According to the verdict issued by Branch 1 of the Aran-o-Bidgol Court, Mohammad Mahdavi Far was sentenced to three years in prison and two years in exile in Sarbaz city for insulting the Supreme Leader. He was also sentenced to 1.5 years in prison and two years in exile in Sarbaz city for propaganda against the regime, for which the maximum punishment will be enforced. He was also acquitted of insulting the founder of the Islamic Republic and disrupting national security. The evidence for the allegations were Mr. Mahdavi Far's critical letters to Ayatollah Khamenei, published on his [Telegram] channel, as well as reports from Kashan intelligence office and the Basij department about him."

The verdicts for both parts of the case were upheld by the Court of Appeals in October and January, respectively.

According to the Islamic Penal Code, and considering all of the sentences, Mahdavi Far had to serve a sentence of three years in prison.
His sentence began on May 27, 2017 and he was released from prison on March 8, 2019 because he had served more than a third of his sentence, and the court agreed with his parole based on an amnesty article. But after his release, he was transferred to Sarbaz border town in Sistan and Baluchestan province.

Saeed Gholamian, Mahdavi Far’s lawyer, explained about the exile on February 21, 2019: “I disagree with the rulings of the Aran-o-Bidgol court about enforcing my client’s exile. I believe that the most severe punishment for my client was the three-year imprisonment, and when they agreed with his parole they should have released him from Isfahan prison on Friday. But he was exiled to Sarbaz right away. Because the enforcement department thinks the exile sentence is not related to the maximum punishment law and is enforceable as supplementary punishment.”

While serving his exile sentence in Sarbaz, Mahdavi Far wrote a letter to the Supreme Leader of the Islamic Republic, Ali Khamenei, asking him to resign. Following the publication of this open letter, he was summoned to the Sarbaz County Courthouse on June 17, 2019.

Talking about the summons and his visit, Mahdavi Far said: "There seemed to be concerns about my connection or the potential connection with anti-revolutionary groups in the region because of completely wrong reports by some security agencies or individuals. In the end, I reassured him that I do not encourage violence and I am doing my best to persuade the Supreme Leader to resign. I do not have incentive or time to do any other extra work. I explained to him that Ayatollah Khamenei is old enough and must step down after thirty years of leadership."

In August 2019, a Statement of 14 Political Activists was signed by some activists, including Mahdavi Far, asking for the resignation of the Supreme Leader of the Islamic Republic.

The signatories and supporters of the statement were arrested and eventually sentenced to prison.

In February 2020, Branch 102 of the Aran-o-Bidgol Criminal Courts 2 tried Mahdavi Far.

According to the verdict, which was announced to Mahdavi Far's lawyer on February 5, 2020, he was charged with "propaganda against the regime" and "inciting people to fight and kill each other with the intent to disrupt the country's security," and sentenced to one and a half years and seven and a half years in prison for each of the charges, respectively.

The court ruled on other charges, including "membership in groups and communities formed to disrupt the security of the country" and "insulting the Supreme Leader and Ayatollah Khomeini," and acquitted Mahdavi Far from all these charges, saying that he had merely issued a statement, and recognizing the principle of innocence and based on Article 120 of the Islamic Penal Code of 1392 and Article 37 of the Constitution, that was insufficient to consider as elements of the indictment.