There are two aspects to this, one in your domain and the other outside it.
If you have a data set, assuming it is valid and accurate, you can analyze it an publish your findings. That is just science. Like any other study, your methodology is important and your conclusions must follow from the data.
But alleging fraud is a legal matter that should only be left to lawyers, courts, etc. It is not your proper role, even though your findings may be interpreted to imply fraud.
If you name companies at all, stick to facts, not allegations. Don't use legal terms, especially legally loaded terms that might lead to a charge of slander, whether justified or not. The company lawyers are better than any you could afford.
Facts, however, are facts, and can be reported and analyzed. Do that, but leave the legal implications to those better placed to follow up on them.
Let me try to be more clear. First, analyzing data seems to me to have no legal issues.
However, I warn the OP not to make statements that can be interpreted as allegations of misbehavior on the part of others. They may have an "action at law" against you if you do that and it will be expensive to defend your actions even if you are correct.
Let others form the conclusions from your research rather than making or implying accusations.
If legal authorities have some evidence of fraud they can act on it. That can bring the courts to bear, but the regulatory authorities have to act first. That would, perhaps, be a criminal matter and it would be out of your hands altogether. (Note that some improper actions handled by authorities are also civil, resulting in fines, rather than criminal. But still it is up to them to make the allegations and follow it up.)
If you make allegations and are sued, on the other hand, it is a civil matter and the courts are only involved in the adjudication of the dispute between the parties. But being sued is not without cost, even if, again, you are correct. If you allege publicly that a large company has committed fraud you may well be sued and the company probably has a highly qualified legal team that will do what it can to shut you up. If you are Jeff Bezos you can fight such claims since you can afford the best lawyers yourself. Otherwise it is a financial life wrecker.
