Gorbachev was known for being more of a lenient ruler of the Soviets. He issued a number of reforms and policies that were much different from his predecessors, including glasnost and the tearing down of the Berlin wall. With these leniencies, the Soviet people were able to express themselves much more fully, especially with film. For years the Soviets had had a strong grip on censorship of movies and did not allow many of them to reach the public. But by 1985, that all changed.
In 1986, three of what would become iconic films of Soviet Russia were finally released to the public after Elem Klimov was elected as head of the Cinema Workers Union: Trial on the Road (1971), Commissar (1967), and Repentance (1984). Each of these films was deemed by the censorship program to be somehow not worthy of being shown to the public.

Trial on the Road is the least controversial of the 3 in my opinion, and it’s a little confusing why it was even censored. The movie is set in World War II when a Soviet soldier defects to the Germans, but when captured by Soviet partisans, switches sides again. He eventually earns the trust of the partisans for his bravery in battle.
The film presumably was censored because of its theme that suggests sympathy for not only a traitor, but for someone who fought for the Nazi army. The Soviets still remembered the loss they experienced at the hands of the Germans, and my guess is that seeing a film in which a Soviet defector becomes the hero was not very ideal.
Whatever the reason, the film was very well received upon its release in 1986, and has received a score of 8/10 on IMDb. This just shows that the Soviet regime obviously did not have the people’s interests at heart, but was trying to save face both domestically and internationally.