That is not concrete evidence. I tjust makes it seem likely that he did it.
Not that your wrong, but many statements today can go a long ways just by even mentioning something. If someone said that they saw a murder, the police arnt going to take it lightly. As for this case about leaving after the murder, agreed that it looked suspicious, and that alone cannot judge a man if he's innocent or not, but it can sure as hell make a case out of it, and with todays corruption, that information alone could probably lead to a trial.