Beron was a founding member and secretary of the SDS (a coalition of multiple opposition groups) when it was formed on 7 December 1989.[3] He was elected to the 7th Grand National Assembly in the first democratic elections in 1990.
The SDS leader, Zhelyu Zhelev, was elected president by the Grand National Assembly on August 1, 1990 and so Beron was elected to succeed him as chairman of the party. His tenure was relatively short lived. On December 4 he stepped down after admitting that he had worked as a police informer under the old regime. Beron was one of 70 MPs who were named in secret documents as having spied for the state security. Evidence was uncovered that he was a police informant code-named Bontcho who kept tabs on his colleagues for the secret police.[4] In his defense he insisted that his police activities served the state and not the Communist Party.[5]
He was one of the few people who signed the Constitution of Bulgaria.
Beron left the Union of Democratic Forces is 1991.
In the January 1992 presidential elections Beron was the running mate of George Ganchev - leader of the Bulgarian Business Bloc. The duo finished third with 853,044 votes (16.8%).
Beron ran for president in 2001 with Stoyan Andreev (from the Bulgarian Union) as his running mate. They finished sixth with only 31,394 votes (1.1%).
Beron was elected to the National Assembly in the 2005 parliamentary election under the ticket of the new nationalist party - Attack. He split from the party in 2006.[6]
Beron ran one last time for president - as an independent this time - in 2006 with Stela Bankova as his running mate. They finished fifth with only 21,812 votes (0.79%).
