Suitably capable regulators are able to inspect, audit and test the code/algorithms of high impact products and services to ensure fairness and safety.
United States: A new regulation, currently in review, would allow the Commodity Futures Trading Commission to inspect the source code of automated trading algorithms.
United Kingdom: The Gambling Commission enforce a standard (PDF) for remote gambling software. Gambling service operators are subject to auditing against this standard.
Regulators may not have the internal skills and understanding to effectively audit code.
Ethics, context and humanity aren’t written into the code.
Code could be written so a product passes an audit but behave differently under normal conditions.
Organisations may perceive code inspections as breaches of their intellectual property rights.