Here comes another (may be irrelavent) question, why could there be out of court settlement for criminal cases? For dispute or civil cases I understand, but how could an organisation (railway prosecutor) determine whether a person deserves going through legal process and judgement while they could be “bribed” by accepting those “investigation costs and compensation” paid by the person?
I’m a layman in terms of laws and I didn’t grow up in the UK so forgive me if my question seems silly
For 95% of offences, anyone is allowed to prosecute them, sort of analogous to how anyone can bring a civil claim. So, just as you are allowed to settle civil cases out of Court, the same applies to criminal proceedings. It's just that it's fairly uncommon outside of the railway.
Now of course there are only a handful of organisations which have the processes etc. in place to bring lots of prosecutions - like the CPS, CMA, HSE, DVLA, SFO, C
rapita on behalf of "TV Licensing" (the BBC), the RSPCA and of course the TOCs. And most of these organisations do have a degree of 'accreditation' in the sense that they are allowed to issue their own summonses (or Single Justice Procedure Notices for summary-only cases).
But in theory, you or I could bring a prosecution for any offence that doesn't specifically state that it must be prosecuted by the CPS or some other specific organisation.
If it sounds ripe for abuse, that's because it is. In my view, private prosecutions should be outlawed, as they are in most countries (including,
de facto, in Scotland) - simply because the conflict of interest is far too great for a private prosecutor to be relied upon to reliably disclose exculpatory evidence, for example. And ultimately criminal law exists to provide punishment for things which 'breach the social contract' - it has no place being used to strong-arm people into paying disproportionate sums to resolve what would be a civil dispute in most other sectors.
At the very least, there should be stronger regulation, including private prosecutors being obliged to follow the same procedures and policies as the CPS - crucially including the public interest test, which is often sidestepped by private prosecutors purely acting in their own interests.