Judge rejected to study a video footage and a police officer who captured Vinahradau changed his testimony.
Young opposition activist Paviel Vinahradau was sentenced to five days in jail on Monday.
The leader of the “Tell the Truth!” movement's youth wing called Zmiena (Change) was found guilty of disorderly conduct.
The wife of Mr. Vinahradau, 23, said that the activist had been arrested at their home at 7 a.m. on September 7. However, two police officers testified in the trial that they arrested the man outside his apartment building, after noticing that he was using obscene language in public.
Aliaksandr Davidziuk, the police officer who is said to have arrested Mr. Vinahradau at his home, denied having done that while testifying in the trial.
The judge rejected Mr. Vinahradau's request for watching video footage from surveillance cameras at the entrance to the Maskouski district police station, which he said would prove that he was brought there not by the policemen who testified against him.
Mr. Vinahradau's wife, Svyatlana, said that the jail sentence would be appealed.
As Paviel Vinahradau was detained on September 7, he has already served 3.5 days of his 5 days' arrest.
In May 2011, Mr. Vinahradau was sentenced to four years in prison in connection with a post-election protest staged in the Belarusian capital city on December 19, 2010. He was among 11 post-election protesters pardoned by Aliaksandr Lukashenka on September 14, 2011.
Since then, the young man has repeatedly been arrested for allegedly shouting obscenities in public places. He had already served a total of 40 days in jail this year before the most recent arrest.
Another Zmiena activist Aliaksandr Arcabyshau was arrested on September 7. He was sentenced to 3 days' arrest on September 10, but he had already spent the whole weekend behind the bars so Aliaksandr Arcabyshau was released immediately.