The Bloc was accused in the Moscow Show Trials of having committed terrorist acts, while in reality that was a fabrication against the opposition.
The former leader of the Left Opposition Leon Trotsky was deported from the Soviet Union, Lev Kamenev and Grigori Zinoviev were expelled from the party, and the Rights were sidelined.
[3]Three groups joined the political agreement that founded the Bloc: the Trotskyists in the USSR, the Zinovievists and the organization of Sten and Lominadze.
"[2] Zinovievist was term applied to those who followed the views of Grigori Zinoviev and Lev Kamenev, who had themselves publicly repudiated opposition activity.
Trotskyist historian Pierre Broué stated that there was no evidence that Bukharin or his close allies like Rykov or Tomsky were participating in any opposition at the time.
Their platform openly called for "the liquidation of the dictatorship of Stalin and his clique"[5] and also advocated for the return of all expelled party members, including Trotsky.
One remark by Trotsky shows they were extremely important allies: “Even in a modest way, they have given us more than anyone on a ‘practical’ line, to be sure, and not politically.” Other letters do not explain what the "liberals" had given to the Trotskyists, nor who any of their members were.
[2] In the Moscow trials, the defendants were found guilty of conspiring against Stalin, of having formed a conspiratorial bloc and collaborated with foreign governments.
When it was discovered that Trotsky had indeed formed a "bloc" with the opposition in the USSR, like the Soviet government claimed, it put the Trials in a new light.
Most historians at the time believed that they were nothing but a campaign to destroy anyone in the party who disagreed with Stalin, but it was clear that it was based on this bloc, albeit exaggeratedly.
[7] In early 2018, some documents belonging to this group were discovered by the Russian Federal Prison service in the Verkhne-Uralsk isolator, where certain opposition leaders, like Alexander Slepkov were imprisoned.