Here are some points for your essay.
1. Democracy without free and fair elections is a farce.
2. The essence of democracy is that people should be able to change the government peacefully.
3. This is not possible if elections are not conducted in a fair manner. Unfair elections would allow even an unpopular government to continue.
4. For elections to be free and fair, there must be a robust electoral roll.
5. The electoral roll should list all genuine voters.