The Panama Papers. The Boston Globe’s uncovering of systemic sexual abuse within the Church. Watergate. Think investigative journalism, and these are just a few examples that come to mind. The stories shock, reveal something new, and more often than not, spark change — even if incrementally.

But what makes these explosive stories investigative journalism?

As the British writer George Orwell said, “Journalism is printing what someone else does not want printed: everything else is public relations.” But while most journalism, even day-to-day breaking news, require elements of investigation, investigative journalism is characterised by long in-depth research that may take months or years researching a single topic.

Such reporters investigate a lead that may uncover corruption, review government or corporate policies, or draw attention to social, economic, political or cultural trends. While conventional reports are triggered by materials supplied by an organisation — say, an announcement from the government or an NGO — investigative reporting mostly stems from a reporter’s initiative. Maybe he receives an anonymous email containing hundreds of unverified files; maybe a long-cultivated contact tells her about a rumour about a corporate conspiracy. In any case, the aim of the investigative journalism is to expose matters of public interest that are otherwise concealed, whether deliberately or not.

A useful guideline as to what constitutes ‘public interest’ is whether a community would be disadvantaged if this information does not come to light, or it would benefit, either materially or through informed decision-making, from such knowledge. Sometimes, information that benefits one community disadvantages another. For example, forest-dwellers may demand better prices if they know the market value of trees that logging companies want to fell. Naturally, the logging industry would not want such information revealed, as tree prices would rise. Public interest stories do not necessarily affect an entire country, and when they do, they are said to be of ‘national interest’. Unfortunately, that term is sometimes used by governments to justify illegal, dangerous or unethical acts, or to discourage journalists from reporting on a significant problem.

Investigative journalism does not happen overnight. It is developed through several stages of planning, research and reporting, and must live up to high standards of accuracy and evidence. Research can take the form of going undercover or drawing conclusions by mining data, but whatever it yields, it must go far beyond simply verifying the original tip. The final story should reveal new information or cast previously available information in a new light, such that it reveals its significance. A single source can provide fascinating revelations, access to insights and information that would otherwise be hidden. But until the story is cross-checked against other sources — experiential, documentary and human — and its meaning explored, it does not classify as investigation.

Investigative reporting calls for greater resources, better teamwork and more time than a routine news report. Many stories are the result of team investigations. But this poses problems for small publications with limited time, money, and staff with specialised skills. A journalist may need to seek grants to support an investigation and get the help of specialists outside the newsroom.

Congolese journalist Sage-Fidèle Gayala weighs the pros and cons of teamwork:

‘It can be productive to work in a small team, where you establish that each participant has a useful specialisation. One can do the legwork, another can research and compile documents, and the third can write up the story. A team has a good chance of working quickly and breaking a story in a timely fashion. But in many countries, newsrooms are not clean. Reporters or editors can be drawn into the traps laid by industry, business or policy-makers, whether these be threats or bribes Many newspapers also have dubious origins, having been funded by one interest group or another. Editors are primary targets, and sometimes the main offenders. When working in such a context, a young journalist may have great difficulty in completing an investigative project.’