I'm not 100% sure of Ukraine, but most democracies have a legal way to impeach a sitting president. If Yanukovich was committing literal treason, acting on behalf of a foreign country, there should have been a slam dunk case for impeachment.

Our government killed 50 people in a train accident because they couldn't be bothered to maintain the safety systems, then immediately ordered crews to the site to cover everything up with dirt so there would be no trace of fuel additives being illegally transported on a passenger train. The courts found no wrongdoing, and they're still in power.

Who's going to impeach them?