Friday, April 3, 2015

Determining Credibility of Witnesses and the Weight of Evidence


Hon. John J. DiMotto

     In every trial, in order to arrive at a verdict, the trier of fact - the judge in a court trial and the jurors in a jury trial - must assess the credibility of the witnesses and determine the weight of the evidence.   It requires the trier of fact to determine what the truth is and who is telling the truth.  

     In the typical trial, there may be a huge discrepancy in what the victim of a crime says happened  and in what the defendant says happened.  For example, in a sexual assault case the victim may testify that the defendant engaged in sexual intercourse by the use of threats and without consent while the defendant may testify that what occurred was completely consensual.  Both versions can not be true, yet the trier of fact must make a credibility determination.  This can be particularly difficult in a case where there is no physical evidence and no outside witnesses.  So how does the trier of fact arrive at is conclusion?  In Wisconsin, we get guidance from case law and jury instructions.

Jury Instruction on Credibility

     In Wisconsin, there is a judicial criminal jury instruction committee and a judicial civil jury instruction committee who have addressed the issue of credibility and they have adopted the same language for criminal and civil cases.  

The instructions set forth that:

1)  It is the duty of the jury to scrutinize and to weigh the testimony of witnesses and
2)  To determine the effect of the evidence as a whole.

The instruction tells the jury to do this it should consider the following factors:

1)  Whether the witness has an interest or lack of interest in the result of the trial.
2)  The witness' conduct, appearance and demeanor  on the witness stand.
3)  The clearness or lack of clearness or the witness' recollections.
4)  The opportunity the witness had for observing and for knowing the matters the witness testifies about.
5)  The reasonableness of the witness's testimony.
6)  The apparent intelligence of the witness.
7)  Bias or prejudice if any has been shown.
8)  Possible motives for falsifying testimony.
9)  All other facts and circumstances during the trial which tend either to support or discredit the testimony.

The jury is further instructed that:

1)  The weight given to the evidence is not to be decided merely according to the number or witnesses on each side.
2)  The jury may find that one witness' testimony is entitled to greater weight than that of another witness or even several other witnesses.
3)  The jury may take into account matters of common knowledge, observations and experiences  in the affairs of life.

The jury is also told to give to the testimony of each witness the weight the jury believes it should receive.

Finally, the jury is told that:

1)  There is no magic way to evaluate testimony, rather
2)  The jury should use its common sense and experience.
3)  In everyday affairs jurors determine for themselves the reliability of things people say and that they should do the same thing as jurors.

    This instruction is an excellent tool to be used in assessing credibility.  This instruction is based on case law.

Case Law on Credibility

     In Geise v. American Transmission Co.,355 Wis.2d 454 (Ct. App. 2014), the court set forth that it is the jury who determines the credibility of witnesses, resolves conflicts in testimony, weighs the evidence and draws reasonable inferences from the evidence.

     In Jezeski v. Jezeski, 316 Wis.2d 178 (Ct. App. 2008), the court stated that it is the fact finder who:

1)   Gauges the credibility of witnesses and the persuasiveness of their testimony.
2)   Resolves conflicts and inconsistency in evidence.
3)   May believe some testimony of one witness and some testimony of another witness even though their testimonies, read as a whole, may be inconsistent.

Furthermore, on appeal, unless testimony is inherently incredible, an appellate court may not substitute its judgment for the judgment of the fact finder.

     In Dickman v. Vollmer, 303 Wis.2d 241(Ct. App. 2007), the court stated that an appellate court will not second guess the trial court's reasonable factual inferences.  It must give deference to the fact finder's conclusions.

     In Pries v. McMillon, 314 Wis.2d 706 (Ct. App. 2008), the court reiterated that the fact finder is "the ultimate arbiter of both the credibility of witnesses and the weight to be given to each witness' testimony.

     In State v. Marinez, 331 Wis.2d 568 (2011), the court set forth that a witness' testimony is always consequential within the meaning of 904.01 [the concept of relevancy].

      In Teubel v. Prime Development Inc., 249 Wis.2d 743 (Ct. App. 2002), the court indicated the the reason the fact finder is the final arbiter of credibility of witnesses and the weight to be given to each witness' testimony is because the fact finder has had the opportunity to observe the witnesses and assess their demeanor.

     In Covelli v. Covelli, 293 Wis.2d 707 (Ct. App. 2006), the court stated that the credibility and weight determination is uniquely in the province of the fact finder because it is in a better position than an appellate court to make such determinations.  The fact finder has a superior view of the total circumstances of the witness' testimony.

     In State v. Kimbrough, 246 Wis.2d 648 (Ct. App. 2001), the court set forth that the fact finder, in determining the credibility of each witness:

1)   Can properly reject even uncontroverted testimony if it find the facts underpinning the testimony untrue.
2)   Even when a single witness testifies, the fact finder may choose to believe some assertions of the witness and disbelieve other assertions.

The court further stated that this is especially true when the witness is the sole possessor of relevant facts.

     In Bretl v. LIRC, 204 Wis.2d 93 (Ct. App. 1996), the court indicated that credible evidence is that which excludes speculation and conjecture..

     In State v. Perkins, 277 Wis.2d 243 (Ct. App. 2004), in addressing the credibility of witnesses and weight of evidence, the court set forth that only if the evidence is inherently or patently incredible will a court substitute its judgment for that of the fact finder.

     In State v. Kienitz, 227 Wis.2d 423 (1999), in addressing the credibility of an expert, the court set forth that the trier of fact:

1)   Has the ability to accept so much of testimony of an expert that it finds credible.  
2)   Is not bound by the opinion of an expert and can accept or reject the expert's opinion.
3)   May accept certain portions of an expert's testimony while disregarding other portions.

     In State v. Turner, 186 Wis.2d 277 (Ct. App. 1994), the court indicated that the credibility of witnesses is determined by:

1)   Words
2)   Tonal quality
3)   Volume and speech patterns

all of which give clues as to whether a witness is telling the truth.  The court went on to say that is is critical that jurors hear the witness' testimony and relate the testimony to the demeanor of the witness.

     In State v. Anson, 275 Wis.2d 832 (Ct. App. 2004), the court reiterated that the fact finder has no obligation to believe everything a witness says.

     In Cogswell v. Robert Shaw Controls Co., 87 Wis.2d 243 (1979), the court set forth that when more than one reasonable inference can be drawn from credible evidence, the reviewing court must accept the inference drawn by the trier of fact.

     In  State v. Kimberly B., 283 Wis.2d 731 (Ct. App. 2005), the court stated that it is the fact finder's task to sift and winnow the credibility of witnesses.


     The determination of credibility and weight of evidence is not a scientific determination. It is made by a fact finder (judge or jury) through the use of common sense and long experiences in life.  It takes into account:

1)   What is said.
2)   How it was said.
3)   Who said it.

Evidence that is credible and worthy of belief is evidence that has a common sense "ring of truth." The statement of the late Justice Potter Stewart in an obscenity case is very applicable when it comes to determining credibility and weight of evidence:  "You know it when you see it."