The court convicted him of organizing a criminal group, illegally crossing the border, and polygamy. From the time of his arrest last May, Shamsuddinov has maintained his innocence, saying the charges against him were fabricated. But his conviction is a heavy blow to his party, which hopes to make gains in Tajikistan's parliamentary elections scheduled for February 2005.
Along with Shamsuddinov, three other IRP members received sentences ranging from 16 to 25 years for taking part in the murder of a chief administrator in Tajikistan's northern Sughd Oblast.
The IRP has supported Shamsuddinov since his arrest, backing Shamsuddinov's claims that the charges are fictitious. IRP officials often mention that since the most serious crimes he was accused of date back to the 1992-97 civil war, the charges should have been rendered moot by a series of amnesties that followed the June 1997 signing of a Tajik peace deal.
IRP Deputy Chairman Muhiddin Kabirov, says Shamsuddinov was sentenced for crimes that have been amnestied. "I think he was sentenced mistakenly," he said. "There were some mistakes in his case. Because even if he has been involved in some armed groups, he already has been amnestied. There is no secret that we have had three general amnesties that applied to all armed groups, including government and opposition groups. And I'm not sure that Shamsuddinov had any connection with criminal bands."
The IRP has reason to be suspicious about the Shamsuddinov case. Shamsuddinov was one of several IRP members who were taken into custody during the last half of 2003.
As part of the 1997 peace deal, the government handed over 30 percent of the positions in government to representatives of the United Tajik Opposition, the government's main military opponent during the civil war. The backbone of the United Tajik Opposition was the IRP, whose leaders made the main decisions during the war and during the negotiations that led to the signing of the peace deal.
Perhaps the greatest concession the IRP gained from peace was official recognition, thereby becoming the only officially registered Islamic political party in Central Asia, a distinction it continues to have.
But the IRP lost some of its places in government in the parliamentary elections in 2000 when it received only 7.5 percent of the votes cast. Recent arrests of IRP leaders like Shamsuddinov will not help the party attract new supporters.
Shamsuddinov's arrest in May was followed in July by the arrest of Kasym Rakhim, another senior IRP member who now faces charges. The head of the Dushanbe Court, Alpomish Akbarov, spoke briefly about Rahim and the charges he faces: "There is, behind bars, a member of the Supreme Council of the Tajikistan Islamic Renaissance Party -- Haji Kasym Rahim, nicknamed Mullo Kasym. He is accused of raping 13-, 14- and 15-year-old girls."
The leader of the IRP, Said Abdullo Nuri, is due to make an official statement on Shamsuddinov's case tomorrow. His press secretary, Hikmatullo Saifullozoda, told RFE/RL's Tajik Service today that the trial of Shamsuddinov is part of an ongoing campaign to discredit the IRP's leadership.
Saifullozoda said the IRP is the only political force that could challenge the ruling People's Democratic Party of Tajikistan, led by Tajik President Imomali Rakhmonov, at the polls next year.
"First, this is obviously to discredit the party's leadership," Saifullozoda said. "Second, society knows that the only party that could challenge the ruling People's Democratic Party in coming elections is the Islamic Renaissance Party of Tajikistan."
One potentially significant point that few have spoken about so far is that most of the IRP members involved in these cases are accused of having committed their alleged crimes in the northern Sughd Oblast of Tajikistan. The IRP had set a goal of increasing its support in this northern region.
Soghd, known as Leninabad during the war years, was the sole region in Tajikistan that was little affected by the war. The people in Sughd Oblast generally support neither the government nor the IRP, but rather their local favorites, like former Tajik Prime Minister Abdumalik Abdullojonov. He and several others have criminal charges hanging over their heads and are in self-imposed exile outside the country.
Sughd, home to some 40 percent of Tajikistan's population, could make the difference come election time, but -- with highly publicized allegations of IRP senior members committing rape and murder -- Central Asia's only legally registered Islamic party is hardly likely to find a large pool of support there.
(Salimjon Aioub of RFE/RL's Tajik Service contributed to this report.)