Scenario: During the first trial, Makoto and Kyoko are starting to figure out what Sayaka's plans were. We've just figured out that Sayaka intended to invite someone to Makoto's room and kill them afterwards. Though, it doesn't seem everyone is on board…
Kyoko: Now do you understand? She wasn't a blameless victim in this.
Byakuya: No, far from it. It's almost as if…she had been planning to commit a murder on her own.
Makoto: N-no way, there's no way she would do that!
Kiyotaka: Agreed, Sayaka isn't that kind of person. Are we certain this wasn't a sneak attack, that seems more likely doesn't it?
Celeste: Don't you realize it yet, Sayaka was planning on framing Makoto the whole time.
Hifumi: What? That makes no sense!
Yasuhiro: Actually, that might be the case…
Aoi: No way, why would Sayaka do something like that?
Monokuma: THE TRUTH WON'T SET YOU FREE!
Monokuma: It would seem as though you are all divided on how this version of events played out! Puhuhuhu…it looks like I'm final able to do something I've wanted to do since this class trail began!
Makoto: Huh? W-what are you talking about?
Monokuma: Hope's Peak Academy is proud to present the world's first morphenomenal trial grounds!
Leon: M-morphenomenal trial grounds?
Mondo: What the hell are you talking about?
Byakuya: Well then, it seems this just got a bit more interesting…
Monokuma: Interesting? More like game-changing, I've been practically begging for you all argue since this whole thing began!
Chihiro: T-that's terrible!
Monokuma: On the contrary, it's actually quite bear-ible!
Makoto: What do I do? I want to believe Sayaka would never do something…but Kyoko keeps insisting she did. Do I trust Sayaka or Kyoko?
[With that final thought, Monokuma pulled out his stunning, albeit narcissistic, key. Inserting it into the contraption that rose from his chair. Turning the tool, the student's stands began to fly up into the air.]
Left Side (Sayaka's Innocent): Kiyotaka Ishimaru / Leon Kuwata / Sakura Oogami / Chihiro Fujisaki / Toko Fukawa / Aoi Asahina / Hifumi Yamada / Sayaka's Picture
Right Side (Sayaka's Guilty): Makoto Naegi / Kyoko Kirigiri / Byakuya Togami / Celestia Ludenberg / Mondo Owada / Yasuhiro Hagakure / "Junko's" Picture
Kiyotaka: The culprit snuck up on Sayaka with a knife, so she defended herself with the katana!
Mondo: If she used the katana, there would've been some of the gold coating on her hands!
Toko: If there was anything on Sayaka's hands, she w-would've washed it off after she escaped into the b-bathroom…
Yasuhiro: Uhh…The water in the bathroom shuts off after 10pm…
Aoi: The sheath of the katana doesn't prove the assailant is Sayaka!
Kyoko: The assailant damaged the sheath. Process of elimination proves Sayaka was the one who damaged it.
Chihiro: Sayaka was staying in Makoto's room, there's no reason for her to plan a murder there.
Celeste: Her reason was so that should could pin the murder on Makoto!
Hifumi: Even if Ms. Maizono was trying to frame Mr. Naegi, he would just foil her plan!
Byakuya: Our dear Makoto wouldn't foil her plan, he isn't capable of that cutthroat behavior…
Leon: Anyway, it's not like there's any evidence it was Sayaka who started the whole thing!
I got this!
Makoto: All the evidence we already looked at doesn't point to a sneak attack, it points to Sayaka attacking first!
[THIS IS OUR ANSWER]