Yamadayev's killing in a beachfront car park in March 2009 stunned Dubai authorities as the first major political assassination in the Gulf city-state.
Yamadayev was a rebel during the first Chechen of 1994-1996, but he switched sides after Vladimir Putin, then-Russian president, sent government troops back into the region in 1999.
He became the commander of the Vostok battalion, a unit of former rebels which played a key role in subduing separatist resistance and was named a "Hero of Russia", the nation's top honour, in 2005.
|Yamadayev fell out with the current Chechen leadership and fled to Dubai [File: EPA]
He later fell out with Ramzan Kadyrov, Chechnya's Kremlin-allied president and left the country, making his way to Dubai, where he lived under a different name.
Dubai police have named Adam Delimkhanov, an adviser to Kadyrov, as the person who organised the murder, but Delimkhanov has repeatedly denied any involvement.
According to court documents, the Iranian defendant was accused of passing a gun to the alleged shooter, while the Tajik defendant provided information to the assassins and later helped two of them flee the country.
Both defendants pleaded not guilty to the charges at their arraignment in August.
Defence lawyers claimed that the police had failed to produce strong enough evidence against their clients and mishandled the investigation by not thoroughly questioning Yamadayev's bodyguards and others in his close circle of associates.
The killing of Yamadayev came just months after the murder of Suzanne Tamim, a Lebanese singer, in a luxury high-rise apartment in the emirate.
But those high-profile murders have since been eclipsed by the assassination of Mahmoud al-Mabhouh, a senior Hamas figure, by a suspected hit squad in January.