Complex sentence: Some people say that by discouraging minority parties, the system acts as a defence against extremist parties such as the BNP; on the other hand, critics believe that the system unfairly discriminates against smaller parties and is undemocratic.
Split into simpler sentences: Some people say that by discouraging minority parties, the system acts as a defence against extremist parties such as the BNP. On the other hand, critics believe that the system unfairly discriminates against smaller parties and is undemocratic.