Liam Stacey was jailed last week for 56 days for tweeting racially offensive remarks about the Bolton Wanderers footballer Fabrice Muamba, who had suffered a heart attack on the pitch.

Previously, accountant Paul Chambers was convicted of sending “a message of a menacing character” contrary to the 2003 Communications Act, for tweeting: “Robin Hood Airport is closed. You’ve got a week and a bit… otherwise I’m blowing the airport sky high!”

The lessons from both cases: if you post on the web, you must realise you are publishing and be very sure about who you are publishing to. Both men were tweeting publicly, therefore publishing to everyone who uses the web. Neither was sharing their thoughts privately and must stand by the consequences.

All of which runs contrary to the recent Market Research Society guidelines for online research. These say that you cannot, for research purposes, use information posted online that was not explicitly posted as part of a research study. Data acquired by searching the web cannot be used, because it is not acquired by the guiding principle of informed voluntary consent. This position not only ignores the burgeoning social media monitoring industry, whose sole purpose is to trawl the web collecting data for research and interactive marketing purposes; it also ignores the purpose of the web, that it is a vehicle for publishing information.

If you publish an article in a journal or get quoted in a newspaper story, you tacitly acknowledge that others have the right to search, analyse, re-quote (accurately) and attribute what you have said. It is sloppy work not to reference sources in desk research. Putting information online should be guided by exactly the same principle.

Moral and ethical judgement and common sense need to be applied, of course. But if the law courts consider tweets to be public domain, shouldn’t the research community?

• Click here to read a response to this article from Barry Ryan, standards and policy manager of the Market Research Society. Also, see What can and can’t you say on Twitter? at BBC.co.uk

Andy Evans is co-founder of Humfish, a software developer building research web applications, and ethnographer and research filmmaker at Exposure Research