The investigation was far from fruitless. After all, the investigation was only conducted this last turn, and I mentioned nothing about it in the OOC, so that holds no water. As well, it does not have any bearing on asking the permission of a nation before coming in and trampling on their own investigation. The real problem here is that I have nothing save for Rakdarian word of honor suggesting that your spies were really only in my country to investigate the assassination, and frankly, the fact that you've already been confirmed to have sent spies into my nation secretly and illegally is a mark against the honor of Rakdar. Also, the fact that you had no intelligence beyond public knowledge is also another mark suggesting that you may have sought to set up a spy ring in my country to obtain such intelligence.
Actually, the funny part is that before I caught your spy, my assumption was that it was a domestic concern, simply because the proximate cause of the assassination
came so soon before the assassination itself, putting it inside the command loop for any foreign capital to have sent orders to that effect. It was only when you admitted outright that you had agents in Rakdar that I realized that general orders to trigger the incident could have been sent in advance, with the specific trigger left up to the agent. Indeed, I actually don't think it was aimed at Serica at all. If my worst-case suspicions are accurate, you didn't care about Serica, but you simply wanted to aim my nation at your actual enemies like a weapon. Put one of your rivals in a long-term war with another equal power, and both sides would be bogged down, at which point you can hit your enemy from an entirely different direction while simultaneously professing support for Serica. If it worked out, you'd have one enemy eliminated and absorbed, as well as a grateful ally ready to help against other rivals. It would have been a very clever ploy. It's not a theory I'm wedded to, as I have leads for investigation that will help further and, even if it were true, there are other nations that would also benefit from a Serican war against the people implicated in the assassination, but the fact that Rakdar is known to have spies in my nation is very suspicious.