Sidorov, the editor-in-chief of the independent daily Tolyatinskoye Obozreniye, was murdered in Togliatti, a city on the Volga River 600 miles (960 kilometers) east of the capital, Moscow.
Sidorov was the second editor-in-chief of Tolyatinskoye Obozreniye to be murdered in the last two years. His predecessor, Valery Ivanov, was shot at point-blank range in April 2002.
According to local press reports, two unidentified assailants stabbed Sidorov several times in the chest late in the evening while he was approaching the apartment building in Togliatti where he lived with his family. The assailants fled after stabbing Sidorov, and the editor died in his wife's arms after she heard his call for help and came down to the entrance of their building.
Journalists at Tolyatinskoye Obozreniye-a newspaper known for its investigative reporting on organized crime, government corruption, and shady corporate deals in the heavily industrialized city of Togliatti-are convinced the murder is in retaliation for Sidorov's work.
"All of our investigative work was supervised by Aleksei," a journalist at Tolyatinskoye Obozreniye told CPJ. Another journalist at the paper told CPJ that Sidorov had received unspecified threats in retaliation for his work.
Government officials initially agreed that Sidorov's murder appeared to be a contract killing in retaliation for his work. But a week after the killing, officials began offering conflicting explanations about the motive for the murder. On October 16, the local head of the Interior Ministry, Vladimir Shcherbakov, said Sidorov was stabbed after refusing to give a stranger a sip of some vodka he had supposedly been drinking, the independent Moscow daily Gazeta reported.
That same day, Deputy Prosecutor General Vladimir Kolesnikov said the murder was related to "the journalist's professional activity," the independent Moscow daily Kommersant reported. But the next day, he switched his story, calling the murder "an act of hooliganism," the ITAR-TASS news agency reported.
According to the local press reports, Samara's Deputy Prosecutor General Yevgeny Novozhylov said that an intoxicated welder from one of the local factories, Yevgeny Maininger, stumbled upon Sidorov that evening and murdered him after a brief argument. Local police detained Maininger on October 12 and charged him with murder on October 21 after he confessed to the killing.
Sidorov's family and journalists at Tolyatinskoye Obozreniye were skeptical that authorities had found the true killer-and a year later, a Russian district court judge confirmed their doubts by acquitting Maininger.
On October 11, 2004, Judge Andrei Kirillov found that the 29-year-old Maininger was not involved in Sidorov's murder and said the prosecution's case was untenable, the independent Moscow daily Kommersant reported.
Sidorov's father said the family was pleased that the acquittal ended what they considered to be a flawed investigation. "The investigation, instead of seeking out the real killer of my son, tried to dump everything on this innocent person," said Vladimir Sidorov, according to local press reports. "We will do everything possible to ensure that [authorities] start a normal investigation."
Karen Nersisian, the defense lawyer representing the Sidorov family, said he will work to have the case transferred to a higher court in Moscow, according to local press reports.