When I served on a jury during a murder trial, the judge explained the concept of dubio pro reo before we started our deliberations. He said that reasonable doubt isn't limited to what we as individuals would find reasonable, but what an imaginary "average person" would believe.
The case hinged on whether or not the defendant acted in self-defense or out of malice for the victim. Some jurors tried to argue that a reasonable person would grab whatever weapon were available to defend himself. Others said that the defendant had several opportunities to leave the situation and chose instead to retrieve a shotgun and kill the victim out of anger.
There was enough reasonable doubt about the defendant's motivation for the jury to find him not guilty of murder. We were all okay with that, because we were told to assume the man was innocent to begin with, and the prosecutor had to prove his motivation to commit murder in court.