Why every revenue dollar matters

For Sierra Leone, extractive revenue carries unusual weight. The mining economy is built around iron ore, diamonds, rutile and bauxite, alongside artisanal gold and diamond production. EITI's latest country data shows extractives contributing about 11% of government revenues and 61% of exports.

In 2023, extractive tax revenues reached about US$41 million, led by iron ore, diamonds and rutile. In a smaller economy with limited administrative capacity, Sierra Leone extractive revenue lost through under-reporting, mispricing or weak reconciliation can therefore have an outsized fiscal cost.

Designed for a different audit constraint

The Multi-Dimensional Revenue Intelligence Algorithm (MDRIA) is especially relevant to low-capacity audit targeting because it does not require a large archive of confirmed fraud cases. Instead, it asks whether a taxpayer's production, prices, costs, royalties, exports and physical activity can all be reconciled.

The framework compares company-controlled declarations with harder-to-manipulate references such as utility or fuel records, customs data, market prices and statutory obligations. The result is explainable audit selection.

From diamonds to rutile: following the physical story

That logic could be adapted across Sierra Leone's main minerals. For diamonds, reported production and exports could be reconciled with licensed activity, valuation records and Kimberley Process information. For rutile and iron ore, declared output could be tested against processing activity, fuel or electricity consumption, shipment volumes and export records.

Diamond rutile taxation then becomes part of a wider consistency test rather than a stand-alone calculation. A royalty may be arithmetically correct while still being calculated on an understated production or sales base.

Why multiple weak signals matter

The paper's central insight is that sophisticated evasion may be spread thin. A company could slightly understate output, reduce export price, inflate costs and adjust its royalty base without making any single number look extreme. MDRIA combines those weak inconsistencies instead of waiting for one large red flag.

Doing more with limited audit capacity

This matters because small economy revenue recovery depends heavily on choosing the right cases. The framework ranks taxpayers under a fixed audit-capacity constraint, allowing scarce investigative resources to focus where several independent facts disagree.

It also avoids relying on a black-box score alone: each selection can be traced to production, pricing, cost, royalty, revenue-feasibility or mass-balance evidence. For mining compliance West Africa, that transparency matters because audit decisions must remain defensible to taxpayers and institutions.

Building on Sierra Leone’s existing data

Sierra Leone is not starting from zero. EITI reporting already reconciles company payments with government receipts, while the National Minerals Agency operates a digital mining cadaster and data repository. EITI has also highlighted gaps in the comprehensiveness of some production and export information, particularly around artisanal mining.

A stronger multi-source system could connect National Revenue Authority filings, National Minerals Agency production data, customs declarations, export valuations, royalty records and independent physical evidence.