The National Crime Agency (NCA) was a national law enforcement agency in the United Kingdom. It is the UK's lead Agency against organized crime; human, weapon, and drug trafficking; cybercrime; and economic crime that goes across regional and international borders, but it could be tasked to investigate any crime.
The NCA had a strategic role in looking at serious crime in aggregate across the UK, especially analyzing how organized criminals are operating and how they can be disrupted.
Clark Newton was a high-ranking officer for the Agency. He had a habit of pursuing cases relentlessly without a care about the person's standing or reach. Sometimes it would work out, but most of the time, these kinds of people were protected from the top, making it harder for him to continue.
In those cases, the reports were leaked through various channels damaging the supposed perpetrator's reputation. At least in this way, he could achieve some justice for the victims.