will she ever be released?

From a superficial reading of her life, probably not. She was found guilty, sentenced to life in prison, and there's seemingly been nothing in the decades since then that throws her guilt into doubt or mitigates her decision to commit murder.

Downs continues to deny shooting her kids at each parole hearing, showing a complete lack of introspection and remorse. Perhaps she'd be released before death if she admitted to and repented for what she did, but her psychopathic ego won't allow that.

All the parole board has to do, if they haven't already, is listen to the taped phone conversation between Diane and Robert Knickerbocker, the married guy she was obsessed with who didn't want kids. In 45 minutes she rants on & on about the legal system and how she's being screwed and how her kids are lying about her being the one who shot them, and how she'll prove in court that her kids are lying and she needs to protect other victims like her from being screwed by the legal system. Not once does she seem concerned or worried about her kids' health or recovery. Remember, her 3 year old son is paralyzed, her 9 year old daughter had a stroke, both almost died, and the other daughter did die. Never mentions any of that, not once, no concern or sadness or grief or how horrible it was that they were shot. In fact she actually says that both of them are absolutely fine! But there IS one thing she keeps repeating throughout the entire conversation, over and over. She keeps telling him, "I'll never get my kids back. They'll never let me have my kids again." She's trying to convince him that now he can be with her. It's unbelievable to hear it. I'm sure the parole officers have. She's not going anywhere.

She comes across as very unpredictable and a pure psychopath. The type who might reoffend.