He gave three different stories as to what happened.
1. Shot at a seal.
2. Found a gun.
3. Accidental discharge.
He always claimed to have
found the gun. The three different stories were that 1) it accidentally discharged
three times, either by accidentally pilling the trigger or by stepping on it, depending on which of his stories you believe; 2) shooting at seals. In either case, at trial (which is all that matters) his lawyers admitted he pulled the trigger bit claimed it was an accident).
Negligent homicide was not on the table. How can you not be quite sure why he wasn't convicted? It wasn't even a lesser charge the prosecutors sought.
Quit digging. You're simply wrong.
Again.
The jury was in fact given the option to convict on the lesser included charge of involuntary manslaughter, which is what California call negligent homicide:
http://www.cnn.com/2017/11/30/us/kate-steinle-murder-trial-verdict/index.html
Try reading up on it a bit. No intent or malice is required, and applies to accidental killings:
Manslaughter is the unlawful killing of a human being without malice...In the commission of a lawful act which might produce death, in an unlawful manner, or without due caution and circumspection.
https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=PEN§ionNum=192.
What version of facts could the jury have reasonably believed thay wouldn't fit that definition, given that he admitted firing the gun thay killed her?
The defendant did not testify at trial, so his version of events came in through his pre-trial statements, where he literally came up with three different versions of how the gun managed to fire. Leaving aside the entire possibility that he did this deliberately. He either 1) stepped on it and it fired three time (impossible), picked it up and it fired accidentally three times (also impossible), or 3) picked it up to shoot at sea anals on the pier, which is prettyuch the perfect definition of negligent homicide.
I'd add again the thought experiment if you changed up the parties here. A white guy convicted of seven prior felonies shoots and kills a black guy in public, tells three different bizarre versions of how it happens, and walks completely. No affirmative defense, nothing.
What would be the reaction?