Let's say you have a very long Chronotech look-ahead. (I still need a better word for this, but this will do for now.) Let's also say that you want to do some research that no research board would possibly approve. For instance, you'd like to improve our ability to handle depression theraputically… by driving people to suicide and watching the process.
So you do it, and you record it, and future-you sends detailed information back. Present-you gets the information and, as Chronotech requires, tests it - but not by this horrible method of killing people. Present-you tests it by applying therapeutic methods to people who have severe depression and helping them overcome it.
Clearly, you have issues. You'd make a horrifying villain. That's sort of a side point for today.
Present-time you, the only you that exists, never killed anyone. You planned to, and you have information that was clearly gained through that method, but those people are alive and may never have even met you. You have no memories of driving them to suicide. The timeline where that torture happened doesn't exist. Hell, depending on how big that look-ahead distance is, present-you may never have even thought of doing this when you got the information.
To me, something awful has clearly happened here. Something that no one else is likely to find evidence of, and that may be quite difficult to write laws around.
