The Soviet-born lawyer and financial expert was detained by the Belarusian security service along with his secretary on arrival in Belarus on March 12, and accused of using forged documents. In late May, Zeltser was officially charged with drug smuggling and possession, and later with industrial spying.
"Minsk's city court, which considered Zeltser's case, found that his culpability in industrial espionage and the use of forged documents was proven," the Supreme Court said.
However, the court absolved Zeltser of the drug possession charges. His secretary Vladlena Funk was also handed a year in jail for illegally gathering commercial information and using forged documents.
Born in the Soviet republic of Moldova, Zeltser emigrated in the 1970s and received his license to practice law in 1990.
He became known for exposing a Russian money laundering scheme carried out via the Bank of New York in the 1990s.
He was also a defense attorney for Pavel Borodin, the secretary of the Russia-Belarus Union State, who was arrested in New York on money laundering charges in 2001.
Zeltser's name recently appeared in the media in connection with a scandal over the estate of late Georgian tycoon Badri Patarkatsishvili, a former business partner of fugitive Russian billionaire Boris Berezovsky.
After Patarkatsishvili died in February 2008, his estate became the center of a legal dispute between the Georgian businessman's wife, supported by Berezovsky, and Patarkatsishvili's distant cousin Joseph Kay, represented by Zeltser.
