Public inquiries are announced in response to events that demand answers quickly, and then report years later. The delay comes from obligations built into how an inquiry must work.
The terms of reference decide the size
An inquiry can only examine what its terms permit, and those terms are set at the outset by the body establishing it.
Narrow terms produce a faster report but risk missing the question people wanted answered, while broad terms invite an investigation spanning decades and many organisations.
Pressure at the announcement stage usually favours breadth, and the timetable consequences of that choice appear years later.
Document collection precedes everything
Inquiries request records from every organisation involved, and the volume runs to millions of pages across incompatible systems.
Each document must be reviewed for relevance, redacted where necessary and assembled into a coherent chronology before any witness can be questioned usefully.
This phase is invisible from outside, which is why an inquiry can appear dormant for a year while its central work is under way.
Fairness obligations add a full cycle
Anyone who may be criticised is generally entitled to see the proposed criticism in advance and to respond to it before publication.
That process runs after the findings are drafted, and the responses can require further evidence, redrafting and in some cases additional hearings.
The requirement is what separates an inquiry from a commentary, and it is also one of the largest single blocks of time in the schedule.
Parallel proceedings force sequencing
Where criminal investigations or civil claims arise from the same events, an inquiry may have to defer parts of its work to avoid prejudicing them.
Witnesses may decline to answer while facing proceedings, and evidence may be unavailable until a court has dealt with it.
Inquiries respond by splitting the work into phases and publishing interim reports, so that urgent safety recommendations are not held back by the parts of the investigation that must wait for a court.
Recommendations are the point
The output is a set of findings and recommendations, and neither binds the government that commissioned the work.
Implementation is tracked unevenly, and recommendations from separate inquiries into similar failures often repeat each other years apart.
That repetition is the standard criticism of the format, and it is why attention has shifted towards mechanisms for tracking whether recommendations were adopted, rather than towards speeding up the inquiries that produce them.