The report jackk gave me doesn't, at least. I don't know whether that information would be available aomewhere.

Then what I would do is this: First, ask if there is a record of the time of the downvotes. If there were a large number over a short time period, you can be very confident that it's karmassassination.

If that information isn't available, then just look at my posts which were downvoted by Senor 150 and compare it to my actual chronological posting history. If there is a long string of chronologically uninterrupted downvotes, you can be very confident that it's karmassassination.