You might be interested in these earlier answers!

How easy was it for fugitives to evade capture in the Roman Empire? by u/mpixieg

How were crimes investigated in Roman times? by u/AwesomeDog59

Prior to DNA evidence, finger prints, etc. how did they solve murders and actually know if they convicted the right person?

I'm living in Ancient Rome and I just murdered someone. What chances do I have of getting caught?

Short answer: murder was considered to be a private matter between citizens. Your family will be responsible for finding your killer and bringing them to court, and only then would the authorities get involved.