From the LA Times:
Paul Theodore Del Vacchio, now 41, is a gambler. In Riverside County Superior Court, a psychologist testifies that Del Vacchio fed his impulse-control disorder with online wagering, not caring about the win or loss, just the high of the bet.
This is why he stole half a million dollars from his employer, an Indian casino, Del Vacchio tells the judge. It was a compulsion. He needed to cover his losses.
Needless to say, the addiction defense didn't work: the Judge handed Paul Del Vacchio a four year sentence. If we aren't going to show mercy for crack addicts, then we certainly aren't going to forgive a thief with a gambling addiction. The Judge explained his logic:
"We can't let everybody who comes in here and wants to use an addiction, whether it be compulsive gambling, whether it be compulsive drinking, whether it be drug addiction, we can't as a society let them utilize that as a method of getting out of their wrong acts. You know, it's like my saying I'm addicted to beautiful women and fast cars, so I get to steal from the court's trust account...."
On the one hand, I agree with this legal decision: a crime is a crime, regardless of the addiction that fueled it. On the other hand, there is a large body of neurological evidence demonstrating that our various addictions, from gambling to cocaine, seriously warp our brain. In particular, they damage our dopamine reward system, which has been implicated in the processing of rewards and decision making. So why does the justice system accept insanity pleas, but not addiction pleas? From the perspective of our brain, both are debilitating conditions that distort our perceptions and judgment. As far as I can tell, the only thing that makes schizophrenia different is its strong genetic component, which is estimated at 50 percent. But this seems like a flimsy distinction, since we now know that susceptibility to addiction is also partly genetic.
Is there another legal factor that I'm not considering?
Yes, you are not considering that the basis for the insanity defense is that if someone doesn't know right from wrong as they commit what otherwise would be a crime, there is no crime. If one has no criminal intent, there is generally no crime committed, sane or insane. If you take something genuinely believing that this object belongs to you, you are not a thief. You just made a mistake. If circumstances are such that you kill an intruder and it turns out that person is your spouse, you are not a murderer if you were fooled either by your insanity or by some reasonable excuse like there was a dangerous intruder, but then your spouse turned the corner instead of the intruder. Of course a jury has to see it that way, that it was an accidental death, not homicide.
This is not compassion for a chronic illness ruining your life. It's the same principle for an acute toxic encephalopathy. If you chose to be intoxicated then that's your fault, and your reckless disregard for what might happen is the basis of your crime. If nothing about it was your responsibility, though, there can be no crime.
Addiction makes it easier for us to steal, but we still know it's wrong. Enough addicts can testify to that for it to be common knowledge. So few courts would allow that as a defense.
The "Twinkie defense" is largely a myth. The argument to defend Dan White from having murdered the mayor and councilman Milk was that Mr. White was psychotic from depression and therefore didn't know what he was doing. Evidence of his depression included his bad eating habits which he fell into when he was depressed. It was not that junk food caused his psychosis. It's just that a creative journalist came up with this catchy phrase. I read about all this in the LA Times a few months after the trial. There were other articles around that time trying to debunk this. They failed. "Twinkie defense" will remain in the language for a long time. It's a myth.
While we're on the subject of Addicted to Gambling: The New Twinkie Defense? : The Frontal Cortex, Some celebrities even show their prowess in card games like poker to produce entertainment for the viewers and winnings for the charity institution they represent.