When there is evidence of a murder or crime, we don't need more evidence anymore to condamned the culprit. Rather, any additional evidence will be used to decide on his sentence. Madara was guilty from the start, and everything Hashi was doing was compromise with him to get peace. This is Hashi did not want neither to kill him, nor to let him kill others. It was pure compromise from hashi. My problem here is that most of you who are asking us to see from others' perspective are not fair. You are actually making a one sided analysis, and you want me to buy it, which I will not do. If you read my reasoning, I considered the two sides, and the conclusion is clear even from today's chapter. Madara also needed to prove that he can be trusted by working with Hashirama for the good of the village. Tobirama and the uchiha did not trust him, and he confirmed their decision by letting Hashirama down. It seems clear to me that Madara think that as long as he is not the one in charge, he cannot agree with Hashi. He was selfish, malicious, and was trying to take advantage of Hashirama's gentleness. Fortunately, Tobirama was there to make his true self appears.
Go back and read all the flashbacks, and you will see the evidences:
1. Madara and Izuna rejected the peace truce proposed by Hashi. Tobirama did not even intervene, and at this time, you could have seen that Bitsuma even did not interfere.
2. Madara threaten Hashimara afterward, as if they were meeting for the first time. Seriously, can you grab anything about his behavior.
3. Hashi said they were superior, and he actually was sending request for truce to the Uchiha. I believe that Madara and Izuna were the ones causing the war after the death of the two sides' fathers. Thus they are the one to be blamed.
4. Madara is the one who led the Uchiha to war against an old friend who was pleading for truce.
Seriously, it is clear that the Uchiha are guilty because of Madara, and as I said, Tobirama is pointing only the truth. A normal person wouldn't place his life in the hands of Madara: this is what Tobirama and the uchiha did.
Note: There is one piece of intel remaining - that is how Madara got Izuna's eyes. Please be ready for this because I think Itachi has proven to be trustworthy. If it comes out that Madara forced Izuna, I wonder what you will say. Again, I think that Madara will never change his mind because of the way he got Izuna's eyes, and the reason he got them.