Thursday, July 31, 2014


Prior Probability is a term associated with a complex mathematical formula devised by the eighteenth century mathematician Thomas Bayes. You most likely will have to look long and hard to find a simple, everyday-English definition of the term.  I did a quick search of all the usual suspects on the internet (Wikipedia, etc.), and the most lucid definition I could find came from 

“The probability assigned to a parameter or to an event in advance of any empirical evidence, often subjectively or on the assumption of the principle of indifference.” Here is my homespun definition:  Prior Probability is a common-sense estimate of the      probability of an event made at the outset of an investigation.

For example, the recent book Abraham Lincoln’s Most Famous Case, investigates three accounts of Abraham Lincoln’s Almanac Trial. The most popular story has Lincoln winning the case with a brilliant cross-examination, another says he won it with a brilliant final argument, and the final version says he won it with unethical trickery. Before conducting any investigation to determine the truth of the matter, which version seems most likely based on what we already know about Honest Abe, the author of the Gettysburg Address? That’s the prior probability. At the end of our investigation, we arrive at the posterior probability—what most likely happened? Lincoln’s Most Famous Case investigates these three versions of the story, and renders a verdict on which story has the most posterior probability.

This is a rather lengthy leadup to advancing the proposition that prior probabilities can help us to craft an effective cross-examination. Although it does not use the term, the 1929 book Cross-Examination of Witnesses (by Asher L. Cornelius) describes a method of using prior probabilities in case analysis.
1.      Write a narrative of the case stating the undisputed evidence and the contentions of the parties in the most neutral, nonjudgmental language possible.
2.      Identify the point(s) of contention.

3.      As to each of the points of contention, make a common sense determination which side of the argument seems more likely (has the greatest prior probability). Write down these prior probabilities and the facts which support them.

4.      Draft a cross-examination aimed at emphasizing the prior probabilities and the undisputed facts supportive of the prior probabilities.

Here is one of the examples used in the book:


Anderson purchased an apartment house from an owner Baker for $65,000 and paid $15,000 down, leaving a balance of $50,000 to be paid on the contract at the rate of $600 per month. Anderson claimed that the owner Baker, from whom he purchased the property, misrepresented the facts in this transaction, in, the following particulars:

(a) That the rentals from this property of $700.00 per month had been reduced so that they were at absolute bed-rock at the time the transaction was closed and that all of the tenants were prompt' in paying same, and that an expenditure of only about $300 per annum was required for heat.

(b) That the owner represented that all of the apartments were in good repair as to decorations; that the building would easily carry the contract and pay for itself out of the rentals.

Anderson purchased the property, entered into possession and discovered the following facts: ,

1. That it cost him $250 per month for heat;
2. That the tenants were not prompt in paying rent;
3. That heating plant required $500 repairs;
4. That the property lacked approximately $300 per month of paying for itself from the rentals.

Anderson brought suit for rescissions against Baker. The defendant in his answers denied that he made any such representations as above set out. -,
What, now, are the probabilities in this case? The lawyer for the plaintiff, in planning his cross-examination of the defendant and his witnesses should reach the following conclusions respecting the same:


(1) Anderson as a purchaser would be vitally interested in knowing what income the apartment produced. Baker, the owner, had that information. Anderson did not. The probabilities, therefore, strongly support the contention of Anderson that he asked for this information. If Baker had given him the actual facts he would have refused to purchase the property. So, here again, the probabilities support Anderson’s claim that Baker misrepresented the income.

(2) Since heating costs of large apartment buildings vary widely, depending upon the efficiency of the heating plant as well as upon the construction of the building, the probabilities are strongly with Anderson when he stated that he asked Baker what the cost would be and Baker told him. If Baker made any representations at all about the heating costs of the apartment, it would have to be a representation consistent with the purchase of the building by Anderson. Had Baker told the real facts, Anderson would not have purchased.

(3) As to the condition of the interior decorations, the individual apartments being all rented, Anderson did not have access to them and he was compelled to depend on Baker for information. Here again a true disclosure would, in all probability, have blocked the deal.

(4) Since the tenants in the building were none of them prompt in paying their rent, and since Anderson naturally would be interested in making inquiries as to their character, the probabilities are that Anderson did inquire and that Baker concealed and misrepresented the real facts.

Since one of the important objectives in cross-examination is to show that the witness is not testifying truthfully, one forceful method of doing this is to show the improbability of his story by emphasizing facts before the jury which render such story improbable. Counsel, therefore, cross-examined the defendant in, this case as follows:

Q. You, as the owner and operator of this property, knew the annual cost to heat this building?
A. Yes, sir.
Q. The heating costs of apartment buildings vary widely do they not, depending upon the condition and efficiency of the heating plant and the construction of the building?
A. Yes, sir.
Q. You had exact information as to what it cost to heat this building?
A. Yes, sir.
'Q. Mr. Anderson, your prospective purchaser, had no information as to what these costs were 1
A. No, sir.
Q. And he, as a prospective purchaser of this building, would naturally be very much interested in knowing what these heating costs were.
A. Yes, sir.
Q. You were ready to answer his questions in this regard?
A. Yes.
Q. And yet he asked you nothing about this important subject?
A. No, sir.

The process described in Cross-Examination of Witnesses is a slightly different method of conceptualizing the analytical process we describe in Chapter 3 of Cross-Examination Handbook, but it uses a similar procedure and arrives at much the same place you would arrive at using our method. Cross-Examination of Witnesses describes a workable analytical mode, and If you feel more comfortable using its analytical framework than ours, by all means do so. Although there is more than one way to skin a cat, the cat ends up flayed no matter how you do it. What Cross-Examination of Witnesses says nothing about, however, is how to go about actually drafting, constructing, and arranging the cross-examination. Chapter 4 of Cross-Examination Handbook fills this void.

Saturday, July 26, 2014


Watch Irving Younger Discuss the Ten Commandments of Cross

Whenever we get to the subject of cross-examination in my law school class and I (Bob) mention Professor Irving Younger the students give me blank stares. None of them seem to have heard anything at all about Professor Younger or his famous Ten Commandments of Cross-Examination. Younger began his legal career in 1958 with a brief stint as a litigation associate in a large New York law firm. It wasn’t long before he took a position as an Assistant United States Attorney for the Southern District of New York, a position which he held until his election as a New York City Civil Court Judge in 1968.  In 1974 he resigned his judgeship and began a distinguished academic career as a law professor at Cornell University. Younger also served as a lecturer on the CLE circuit, and his most popular presentation had to be his presentation on the Ten Commandments of Cross-Examination.

Younger was a dynamic, charismatic speaker who always entertained while he was educating. Everyone who practiced trial law from the mid-1970’s through the 1980’s knew and used Younger’s Ten Commandments (his Commandments are discussed in Cross-Examination Handbook along with exceptions to the Commandments). Younger died in 1988. Twenty-first century trial lawyers can profit by knowing the commandments, and there could be no better way to teach those commandments than to let Younger tell you about them himself.

Click here to watch Professor Irving Younger holding forth on the Ten Commandments of Cross-Examination.

Saturday, July 19, 2014

Videos of Cross-Examinations

Yogi Berra is supposed to have said “You can observe a lot just by watching,” and that is not a bad method of learning the principles and techniques of cross-examination. You sometimes even learn more from watching a wretched cross-examination than you can from watching a brilliant one. Set forth below are videos of cross-examinations performed in celebrated trials both recent and historical. In the videos you will see examples of both wretched and brilliant techniques.

Amanda Hayes stood trial for helping her husband kill and dismember his ex-wife. She defended herself by claiming that she was an innocent victim of circumstance who knew nothing of the murder until her husband told her about it and enlisted her aid in disposing of the body.
Amanda Hayes Cross-Examination

Jessie Dotson stood trial for the mass murder of his brother and five other people. The State contended that he killed his brother in an argument and then killed the others in an attempt to eliminate witnesses.
Jessie Dotson Cross-Examination

Jodi Arias stood trial for killing her boyfriend Travis Alexander, who was found dead in his home with 27 to 29 stab wounds in his body. Arias claimed she killed Alexander in self-defense.
Jodi Arias Cross-Examination, Day 1, Part 1
Jodi Arias Cross-Examination, Day 1, Part 2
Jodi Arias Cross-Examination, Day 1, Part 3
Jodi Arias Cross-Examination, Day 2, Part 1
Jodi Arias Cross-Examination, Day 2, Part 2
Jodi Arias Cross-Examination, Day 2, Part 3
Jodi Arias Cross-Examination, Day 3, Part 1
Jodi Arias Cross-Examination, Day 3, Part 2
Jodi Arias Cross-Examination, Day 4, Part 1
Jodi Arias Cross-Examination, Day 4, Part 2
Jodi Arias Cross-Examination, Day 5, Part 1
 Jodi Arias Cross-Examination, Day 5, Part 2
Jodi Arias Cross-Examination, Day 5, Part 3

Michael Dunn stood trial for murder and attempted murder for firing multiple shots into an automobile which was playing music too loudly to suit him. Dunn claimed he acted in self-defense. The jury convicted him on the attempted murder counts but hung on the murder count. Dunn awaits retrial on the murder charge.
Michael Dunn Cross-Examination, Part 1
Michael Dunn Cross-Examination, Part 2
Michael Dunn Cross-Examination, Part 3
Michael Dunn Direct Examination

Hermann Goering, who at one time was Adolph Hitler’s right-hand-man, stood trial at Nuremberg for war crimes and crimes against humanity. Goering proclaimed himself to be “not guilty in the sense of the indictment.” He testified that he was blindly loyal to Hitler and completely ignorant of the Holocaust.
Nuremberg, Cross-Examination of Hermann Goering, Part 1
Nuremberg, Cross-Examination of Hermann Goering, Part 2
Nuremberg, Cross-Examination of Hermann Goering, Part 3
Nuremberg, Cross-Examination of Hermann Goering, Part 4

Oscar Pistorius, the “Blade Runner,” stood trial for the murder of his girlfriend. Pistorius claimed that he accidentally shot his girlfriend in self-defense when mistook her for a burglar.
Oscar Pistorius Cross-Examination, Appears to Change His Story
Oscar Pistorius Cross-Examination, Summary

Mark Fuhrmann was an L.A.P.D. officer who participated in the investigation of the murders of Nicole Simpson and Ron Goldman. Fuhrmann discovered key evidence in the case, and the defense attempted on cross-examination to establish that he fabricated the evidence because of his bigotry and racism.
Mark Fuhrmann Cross-Examination