Without looking at evidence we can't even tell if a murder took place at all. Find a body and try to figure out was it murdered? Look at it. Is there a bullet hole in the back? A knife in the front? Is there, to be short, any evidence that the person didn't die of natural causes?
Because, if there isn't, we won't look for a murderer. If there is, then we have to start gathering evidence to work out who the murderer was. And we don't randomly accuse people, unless we're really bad at this, we look for a suspect that the evidence tells us is guilty. It's a type of puzzle. Did this person die as a result of someone else's actions? If they did, then what happened?
The current diversity of life is a puzzle. Where did it all come from? So people, interested in the truth, went looking for evidence to explain that puzzle. Many of them were Christians, and many of those had a suspicion that the answer to that puzzle was found in Genesis, but when they gathered the evidence, they found Genesis wasn't supported by the evidence.
Evolution is supported by all available evidence.
And Darwin, as the initial prosecutor, started off with a killer case. But he hasn't been the only one. A lot of other people have joined in looking for a suspect and have gathered a lot more evidence than Darwin could have dreamed of. And even though Darwins case turned out to be pretty solid, solid enough to still be convincing, the new evidence is even more impressive. It's so good that we can even make guesses about what evidence we'll find in future, and so far even that is working. Darwin did the same, by the way, making a guess that there would be found a creatre with particular features. It was a type of moth, as I recall, and it was found after Darwin made his prediction.
If another explanation actually worked better, we'd have a new suspect. And if someone actually came up with a better explanation they'd be a certainty for a Nobel, the cash prize and assorted magazine covers. They'd also go down in history. So, with fame, fortune and not to mention the clearing evolution of it's 150+ years of being the only viable suspect, I've got to wonder why no one has managed to come up with something that better explains the evidence.
We have a "crime" in the diversity of life, and we have a "suspect" in evolution. Evolution is guilty, beyond a reasonable doubt.
And, by the way, the origin of life isn't part of evolution. That's a seperate field, known as Abiogenesis. Evolution doesn't care where the life came from.