Steven frowned. As far as he could see, there was nothing on the trunks that pointed to the killer. Not that he expected anything too obvious, but still it was a disappointment. Still though, there was one thing that bothered him. Surely Erin didn't take these oversized trunks himself. Wearing slightly oversized bathing clothing is one thing, but this? That just didn't make sense. So why were they here?
...No. Maybe he should think the other way around. Instead of looking at what is there, he should think of what isn't there; namely, Erin's own swimming trunks. Why aren't they there? The killer took them. Why did the killer took them? There was something on them that pointed to the killer. Which meant that if they found the real trunks, there was a good chance they also found out more about the murder... Of course, the next problem was actualy finding it, but eh.
Similarly, that trail of pills leading towards the locker room -- or possibly the other way around.
Why did the killer not remove it? Did he just not notice he left it? Possbly, but unlikely, given that he went out of his way to go for strangling to not get blood all over himself, something that ended up causing the fall of the last two killers. So... maybe it was a distraction instead? Then maybe there was something in the other locker room, the ladies' one? No, that was impossible; the killer was undoubtly male by virtue of only males being left (unless one of them was a crossdresser, of course; as unlikely as that seemed to him, it wasn't as if he saw Isaac or Tanami without their clothes, and even Norio had kept his underpants on [thank God !), and males weren't allowed access to the girls' locker room -- or so he assumed, at least. After all, why bother making split dressing rooms complete with an electronic lock if guys can just enter the girls dressing room and vice versa?
...Wait, no, of course it wasn't impossible, not if the scanners just checked the PDA instead of who carried it. And though the rules banned lending out your PDA to someone, it said nothing about borrowing it from someone else. So all the killer had to do was take one of the dead girls' PDAs, and he'd be safe. Next problem, getting in himself. Wait, didn't Norio get Monokuma to open Isaac's room before, even though he didn't have his PDA? Maybe he could try that too? It's not like he had anything to lose by trying...
..."Hey, Monokuma? Are you listening? Could you open the girl's locker room door? For, you know, a fair trial and stuff.", Steven spoke to the nearest camera