Search engine manipulation can swing votes: US study

"If two candidates were both trying to push their rankings higher, they would be competing, and that's fine," said Epstein in a release.

"But if Google, which has a monopoly on search in India, were to favour one candidate, it could easily put that candidate in office by manipulating search rankings, and no one could counter what they were doing.

"Even if without human intervention the company's search algorithm favoured one candidate, thousands of votes would still be driven to that candidate."

"Of particular concern," Epstein said, "is the fact that 99 percent of the people in our study seemed to be unaware that the search rankings they saw were biased."

"To prevent undue influence, election-related search rankings need to be regulated and monitored, as well as subjected to equal-time rules," he added.

In response to Epstein's latest research, Google officials as cited by the Washington Post stated: "Providing relevant answers has been the cornerstone of Google's approach to search from the very beginning.

"It would undermine people's trust in our results and company if we were to change course."