With his dilapidated Mumbai office, heavy gold jewellery and a gnarly scar on his little finger — which someone tried to slice off “with a chopper” — Sanjay Rasalpatil, one of India’s leading private eyes, seems an unlikely custodian of democracy.

Business is good, Mr Rasalpatil, 40, told The Times across his cluttered desk. His staple work — vetting brides and grooms for arranged marriages and tailing cheating spouses — is ticking over nicely. But the onset of India’s general election, the world’s biggest and, possibly, sneakiest, has landed him a bonanza.

“We are doing so much work for political people: investigating local leaders, gathering opinions, shadowing voters that might be registered twice, checking rumours.”

Mr Rasalpatil, who heads the DSP Bureau, which claims to be one of the country’s largest private detective agencies, said. “You see, nobody is trusting anybody these days.” Similar tales abound as India’s gumshoes reap a boom in business from the month-long polls, the results of which will be known on May 16.

The country’s 18,000 private detectives have been flooded with requests from political parties to probe the backgrounds of rivals and monitor dissidents within their own ranks, says Kunwar Vikram Singh, the head of the Private Detectives Association of India.

Mr Singh puts the increase in demand for investigators down to the emergence of hundreds of small parties and the rise of coalition politics — something that has raised competition for votes, parliamentary seats and the number of politicians ready to resort to dirty tricks.

A surge in media stings on politicians has also added to the detectives’ workloads and boosted demand for counter-surveillance specialists.

During campaigning, several high-profile political candidates, including Varun Gandhi, the grandson of Indira, have been covertly recorded delivering allegedly illegal hate speeches. Others have been filmed doling out cash at rallies in apparent attempts to buy votes. Mr Singh says that private investigators have played an unsung role in most of these revelations, helping to create “a culture of fear” among would-be MPs. Hoping to cement its place in the political process, the Private Detectives Association has written to the Election Commission of India, the official body entrusted with ensuring a free and fair poll, to formally offer its members’ talents.

“We have the expertise to track the movements of candidates, which can help ensure a fair election,” Mr Singh said. The commission has yet to respond. A quarter of India’s current MPs have criminal backgrounds. About the same proportion of candidates in the election are campaigning under pending court cases.

Attitudes to the rise of the sting culture are mixed. Critics say that little evidence admissible in court has been gathered and few convictions have followed. Others say that anything that keeps India’s leaders on their toes should be applauded.

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