Tuesday, December 06, 2011

Expert evidence requirements

The family court relies on experts in ways that would never be acceptable in a real court that followed rules of evidence. The Federal rules of evidence say:
Rule 702. Testimony by Expert Witnesses

A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:

(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;

(b) the testimony is based on sufficient facts or data;

(c) the testimony is the product of reliable principles and methods; and

(d) the expert has reliably applied the principles and methods to the facts of the case.
First, the expert must be qualified. Having a PhD in psychology is not a qualification unless there is some issue in dispute where the psychologist has specialized training. For example, if the mom is accused of having a borderline personality disorder, and the psychologist is trained at making a DSM-IV diagnosis, then he would be qualified to give an opinion on that. But if he is trained to advise men on coming out of the closet and the court issue involves setting an alarm clock, then he is not qualified.

Next, the purpose of the testimony is to help the judge understand the evidence, and not to draw conclusions about the outcome of the case. So if the mom says that her manic episodes are controlled by drugs, an expert might explain the practical meaning of that.

The expert testimony should be all about how generally accepted principles and methods apply to the facts of the case. The expert should be explaining, not drawing conclusions or writing orders.

The expert does not necessarily have to determine the facts. If some key fact is under dispute, he can simply state his assumptions, and explain how his analysis would differ depending on whether his assumption is correct. Eg, an expert might say that the blood on the crime scence does not match the defendant, assuming that the samples were collected properly. The defendant is free to argue that the assumption is invalid, in which case it should be obvious how that affects the expert's opinion.

Most states have adopted the federal rule for expert evidence. California has not, and still uses and older rule. The difference is not significant to my points here. I cite the newer rule because it is more clearly written, as it has been refined several times over the last 20 years.

When you get an expert forensic report, the first things to look for are the assumptions, the principles and methods, and the explanations of how those principles and methods were applied to the facts. Everything else in the report is just inadmissible fluff.

I have yet to see a family court report that even satisfies these bare-bones requirements for admissibility as evidence. Have you? For those of you who have had the misfortune of being subjected to one of these reports, what percentage of the report contained admissible evidence?

6 comments:

Anonymous said...

in both instances of my CPS investigations as well as court mandated counseling there would be 0% because it was all hearsay as well as poorly derived conclusions from social workers and lower level educated (not PhD) counselors who were not certified by any board.

Anonymous said...

My experience altogether! A CASA friend, among others, advised filing a complaint with CPS, 'They might not be able to do anything, but they always investigate.' Well, no they don't. They'll just file it or throw it away saying: 'Gradmother has concerns.' How is it that there is no one overseeing these incompetents? A complaint to the BBS (Board of Behavioral Sciences) is taken personally by workers for the BBS, who then do nothing expect treat the complainer as the guilty person. They do nothing expect save their own skins. This is the same for Santa Cruz County and the Family Law Court who will do everything to keep from doing their jobs. From County workers to Judge Morse, they only seek to protect their jobs.

Anonymous said...

the problem is that so many of the groups involved in family law, from judges and lawyers to the various counseling and child protective and support services are all "self-policing". There are no outside parties involved in the investigation boards.

In contrast, consider what medical researchers in academia have to go through: a committee compromised not only of other researchers but also w/members of the general public for any clinical or animal based research. As a long time medical researcher myself I've found that to be a very good idea because it does make you think twice about what your doing and whether or not the experiment will bring any real benefits. The scientists and MDs can't always see the forest because of the trees.

Anything that affects seriously the lives of humans really should be under a microscope in terms of scrutiny. The idea floated here in the comments of setting up a petition for video cameras in all the court rooms -including family law- is an excellent idea and I would support the petition to the point of trying to collect the signatures.

George said...

That is an interesting comparison. If I want to do experiments on hamsters, then an oversight committee will review whether the project is worthwhile and ethical. But that sort of critical thinking seems to be lacking from family court and CPS.

Anonymous said...

those regs on ethics committees and their composition came about because of a lot of lobbying. In general, academia started the ball rolling by establishing them voluntarily, then eventually laws were made. So in short, like any sort of change that has to be made to the status quo it has to be a concerted grass roots effort. Those committees, btw, aren't perfect, but by and large they do prevent a lot of potential problems. Same thing w/"informed consent". And I'm speaking as a long time medical researcher, too. Checks and balances from outside "the guild" are OK with me. If I can't explain the necessity of what I'm doing to a "civilian" then I probably shouldn't be doing the experiment because I really don't know what it means. Slows things down a little, but it's for a greater good and hews closely to one of the Hippocratic principles: First, do no harm.

Anonymous said...

you also have to remember a lot of why the critical thinking is lacking w/the CPS and family law types is because they tend to be the Carrie A Nation crusader types. And thus they are filled w/self-righteousness to create social justice, ain't no higher brain functions engaged cuz "I beeeleeeev". No wish or desire to get to understanding the roots of the problem, just weed whack away.

Just my observation, YMMV.