Steinle’s killer was convicted of a couple of charges and his past record had no influence on his sentencing.
You lamented his past history wasn’t brought up in his trial
It rarely is in anyone’s
The bacon guy had his history brought up at sentencing not trial
At rape trials lawyers have tried past history like she was a whore etc
It is almost always not allowed...it’s called character evidence
Trial evidence should usually only be about that specific charge .....this notion is actually a concept of free people’s even though you understandably didn’t like that it didn’t come up but if you allow character evidence at trial then it’s a very slippery slope to exploitation by political district attorneys
Here is a brief explanation from SIM
http://criminal.findlaw.com/criminal-procedure/character-as-evidence.html
And to be of further help I’ll ping a lawyer who can say it better than a car wash owner