The Prosecution's Big Gun

The prosecution is back on the attack in the Andrea Yates trial and they've brought out a big gun in Dr. Park Dietz. In a CBSNews.com Commentary, Legal Consultant Andrew Cohen says Dietz seems to relish his time in the spotlight.

In court on Thursday, he said on the stand that he thought Russell Yates, the defendant's husband, had given him the nickname although I suspect he had it long before Russell and Andrea Yates entered Dietz's life.

Whatever the good doctor thinks of it, it's an apt nickname, but not because of what Dietz does when he's not opining about whether one criminal defendant or another is sane or not.

It's an apt nickname because Dietz seems on the stand to be a fairly arrogant and cocky sort of fellow, the sort of fellow who would tell a jury he just met, for example, that he "stopped counting" the number of cases he's worked on at 1,000 in 1979 or 1980. That means, he quickly added, that he's been involved in "thousands."

Dietz, who began to tell jurors Thursday that Yates knew right from wrong last June when she drowned her children, looks and feels like the "Big Man on Campus" and for that reason, he's a perfect match in this trial with the lead defense expert, Dr. Phillip Resnick, who looks and feels like the school nerd.

It's Mulder (Dietz has a long association with the Federal Bureau of Investigation) versus Quincy. Both men have styles that are as dissimilar as their conclusions. Resnick, the genius, thinks Yates is legally insane. Dietz, the genius, thinks she is not. Soon the jury will decide.

Dietz's procession to the stand after all the acclaim for his reputation and the foreshadowing of his testimony has been a little under-whelming. That's mostly because the gist of his conclusions won't be offered to the jury until Friday, when the state continues its direct examination of the one expert in this whole trial who will tell jurors in a definitive fashion that Yates knew what she was doing last June and knew that it was wrong, to boot.

But what Dietz has told the jury so far already has offered them a starkly different version of the story of the months and years leading up the drownings.

Mostly, it seems, Dietz has taken the same set of data and viewed it through a prosecutor's prism. What defense experts saw as evidence of psychosis Dietz sees as evidence of a lack of psychosis. What defense experts saw as Yates being unable to help herself Dietz sees as Yates being unwilling to help herself.

His testimony so far is entirely consistent with what you would expect from someone who was hired by the prosecution to make a case for legal sanity. There is nothing inherently wrong with this. Dietz may be perfectly correct. But it's fascinating to me after hearing from all the various defense experts that there could be such a completely contradictory spin placed on the same core set of facts.

And they say the law is an impure science.

It turns out, according to Dietz, that Yates wasn't precisely the hapless victim that the defense has portrayed her to be. She didn't take her anti-psychotic medicine when she was supposed to and didn't level with her doctors about what her symptoms were.

She was "thinking she knows best," Dietz told jurors, "she won't take the medicine unless she wants to." He thinks she was and is schizophrenic but not psychotic.

And the combination of Andrea Yates and her husband Russell wasn't so hot, either, Dietz told the jury. Together the couple twice decided not to permit Andrea to have electro-shock treatment. Together the couple decided to ignore the advice of their doctors when it came to having another child. The Yates's were told that Andrea's post-partum depression almost certainly would re-occur if she had a fifth child and, of course, Yates had that child with tragic results.

I'm sure that on Friday Dietz will get around to pointing one of his big Ivy League fingers at the defendant, but so far his testimony seems more critical of Russell Yates. Many of the "stressors" Dietz attributes to Yates' decline were related in one way or another to actions or decisions taken or made by Russell Yates.

First the doctor testified that no family with three children and an infant should live on a renovated bus the way the Yates' did in 1999 -- and he seemed to blame that unhappy condition on Russell, the bread-winner.

Next, Dietz told the jury that home-schooling three small children when there also is a baby in the family doesn't help a depressed mother -- and he seemed to blame that on Russell too.

Mostly, though, Dietz blamed Russell for simply not being sensitive enough to what was happening to his wife in 1999 and 2000. Apparently Andrea told Russell she was feeling depressed and overwhelmed in 1999 and his response was simply to send her to her folks' house, where she promptly tried to commit suicide by swallowing her father's sleeping pills.

Then, after another scary episode, Russell Yates finally relented and bought his wife a house -- while she still was in the hospital and without her seeing it. Then, when his wife told him she thought there were cameras in the ceilings of that home, Dietz said that Russell told Andrea not to worry about it and never told her doctor about such paranoia.

The good thing about Dietz's presence at the trial is that it's a sign that jurors soon will know as much as is humanly possible about why Yates killed. It's also a sign that jurors in the case have been treated to an extraordinary display of academic and intellectual firepower. That's right. I'm not saying Dietz isn't smart. I'm just saying that not everyone likes a wiseguy.