It's a thought experiment. There are surely cases in life in which you know for sure that crime is being committed. What you're asking for though is that due criminal process be a part of denying a payment. Which seems extremely heavy handed.
If my payment processing company doesn't want to help sell guns, or help with human trafficking, or hell, doesn't want to support the meat industry, then I should be able to run my business according to those ethical choices. My company isn't sending someone to jail. They are just refusing to accept a payment. There is no need for due criminal process to refuse a payment.
Should it be illegal to start a vegan payment processing company?
These are the cases of having evidence, right? Which should be reported.
> I should be able to run my business according to those ethical choices. My company isn't sending someone to jail. They are just refusing to accept a payment. There is no need for due criminal process to refuse a payment.
And if two or three large businesses cover 99% of a given market (payment market), how about some anti-monopolistic legal protections? Them colluding to stop the meat industry, continuing your example, would be a monopolistic practice.
Yes, that's the actual problem. Breaking up the existing near-monopoly and creating a functioning market with thousands of competitors would be a far better solution than trying to force the existing payment processors to process all payments, regardless of risk or ethical considerations.
If you think something might be for human trafficking, you report it to law enforcement and let them deal with it. They'll gather evidence, build a case, make arrests, and hand things off to a DA/prosecutor who will file charges. Or, at some point, someone will decide it's not human trafficking, or at least that there isn't enough evidence to prove it beyond a reasonable doubt, and drop the case.
All that is just due process, and a payment processor should not be given that responsibility. Both because I don't think they'd want it (it costs money and carries liability), and because we shouldn't trust them with it (private corporations shouldn't be allowed to apply the force of law).