The national association of pollsters, APEIM, says members will not publish any further results in the run-up to presidential elections on 10 April unless the JNE overturns its ruling, which threatens to rob respondents of the anonymity that is the cornerstone of survey research.

Supporters of the JNE ruling say it will improve transparency and accuracy, but presidential front-runner Alejandro Toledo worries, as pollsters do, that it will undermine the democratic process.

According to a Reuters report, Toledo said: “I strongly protest this act, which seems totally unconstitutional, not at all democratic, and which could be the first step towards electoral fraud.”

Thomas Petersen, a past president of the World Association for Public Opinion Research, condemned the move. He said: “It is very clear that any attempts by governments or other authorities to get access to the personal data of the respondents of an opinion poll are not acceptable.

“Confidentiality is an essential rule in survey research. It is necessary that respondents can phrase their opinions without having to fear any consequences.”

He said polling institutes must be ready to disclose their methodology, but not the personal details of their survey participants.

APEIM is expected to meet with the JNE this week to appeal the ruling.

Peruvian pollsters faced similar threats to respondent anonymity last year when politicians proposed a law that would give them the right to observe survey interviewers in action.