Joyal survived the shooting and is in a hospital in critical condition.
The shooting occurred four days after Joyal said in a television interview that Russian President Vladimir Putin's government was involved in the death of former Russian security-services officer Aleksandr Litvinenko.
In the interview, Joyal accused the Kremlin of participating in a conspiracy to silence its critics.
Litvinenko, a Kremlin critic, died in London in November after being poisoned with polonium-210.
Joyal, a Washington-based consultant, is known for his expertise on the former Soviet Union.
(AFP, washingtonpost.com, ft.com)