IRE HandbookIt is a question that still provokes argument, even among investigative reporters. Some say investigative reporting is nothing more than a trendy name for good, old-fashioned reporting of the hard-nosed, lots-of-shoe-leather school. They may be right. But many of us believe that investigative reporting can be classified and defined:
It is the reporting, through one's own work product and initiative, matters of importance which some persons or organizations wish to keep secret. The three basic elements are that the investigation be the work of the reporter, not a report of an investigation made by someone else; that the subject of the story involves something of reasonable importance to the reader or viewer; and that others are attempting to hide these matters from the public.
Fleeson:AIM high. dig. deepCommon definitions include stories that:- Contain original work, not leaked investigations from law authorities;- Show a pattern of systemic problems, not just one isolated incident affecting one individual;- Right a wrong;- Explain complex social problems.- Reveal corruption, wrongdoing or abuse of power.
Journalism primer
But much of what we call investigative reporting differs in important ways from routine reporting. These differences include:

Usually investigative reporting is undertaken with the idea that some action should result, that some change should be made. We will see that there are exceptions to this and sometimes a thorough investigative story might lead to reaffirmation of what is already being done and an appreciation of it by the public.
Usually investigative reporting is in a longer for-mat and takes a longer period of time to prepare for, to gather information for stories, and to write.
Almost always an investigative reporting effort takes more resources in staff time and in money, since the stories are deemed of more than routine importance.
Frequently investigative reporting is undertaken, not just to do a factual report on a subject, but with the idea that change needs to occur, that reforms need to be carried out, or wrongs corrected. Thus, before the project starts, the publication, its management, editors and reporters, all must be in agreement to spend the time and money to do the project.
Usually, investigative stories will also involve some special promotion ahead of time to alert readers or viewers or listeners, some special "packaging" to make the material especially attractive and upon occasion, special distribution of the stories through reprints, special editions or special sections.
Usually, more attention is also paid to illustrating the investigative stories with good photographs, drawings, graphs, line-drawings or charts and maps, or with outstanding video or audio.
And usually, the most experienced reporters and editors are given the assignment to work with the investigative project, since it is considered one of the most difficult types of journalism to carry out successfully.
Almost always, decisions will have to be made by high-level policy-makers of the mass medium involved. This is because the publication in a way assumes a stance either criticizing or approving of the situation being investigated. More is at stake here than routine, non-involved story-writing.