Now the Central Bureau of Investigation hints that it will at last prosecute Ms Mayawati for corruption over evidence of huge growth in her personal assets.

ECONOMIST: Caste in India

Montreal's city hall has been raided by anti-corruption police seeking evidence of fraud and breach of trust.

BBC: Montreal city hall raided by anti-corruption police

The research is instructive for economists sceptical that clear-cut evidence of corruption can ever be found.

ECONOMIST: Economics focus