5 Scientific Evidence in Court WILLIAM G. ECKERT RONALD K. WRIGHT The culmination of the collecting, cataloging, photographing, investigating, and testing of scientific evidence is its presentation to the trier of fact in court. In the English-American system of law, scientific evidence is thought of as somewhat novel, even though the use of such evidence dates back to the colonial period in the United States. 1 In this chapter we will review briefly the organization of courts in the American system of justice and trace the method by which scientific evidence is admitted into evidence. Types of Courts: Equitable, Admiralty, Law, Coroner, Grand Jury, State and Federal To understand evidence and its use in court, it is first necessary to understand differences in types of courts. In England there were two major court systems, equitable and legal, with the rather late development of a third, the admiralty courts. In the United States, these three courts have merged. The coroner court remains in those state jurisdictions which have retained the coroner system. Grand jury courts remain in both the federal and state systems. Equitable courts come from an ecclesiastic tradition. In England these were the courts of the church. The courts had powers of injunction and mandamus. They could order persons to stop doing what they were doing (injunction) or force them to do what they were not doing (mandamus). The equitable courts were generally maintained after the American Revolu- tion in the United States, but were non-ecclesiastic because of the secular nature of the governments of the United States. In time, states merged the equitable courts with legal courts. The federal government never had separate equitable courts. Today the largest remaining area of strictly equitable court activity is in divorce actions which are always equitable. In equitable courts the trier of fact is the judge sitting without a jury. Because the equitable courts did not have juries before the American Revolution, equitable courts ©1997 CRC Press LLC do not have juries today. We will see later in this chapter how this alters the presentation of scientific evidence because of the fear that the jury will be contaminated by being supplied with certain improper information. If there is no jury, there is less of a fear that the judge sitting as the trier of fact will be so easily swayed by improper information. Admiralty courts were established in England as a separate system, pri- marily to support the ocean-going trade which developed during the mid- to late-16th century. The courts of law (or common law as it is often called) were deemed too tradition bound and rule ridden to allow easy resolution of the disputes which arose in ocean-going international trade. Thus the courts of admiralty were established, again without juries, as juries were thought to lack the sophistication to understand these novel and complicated issues. Following the American Revolution, the federal court system assumed the role of the admiralty courts in England, retaining the judge as the sole trier of fact. Courts of common law were the courts dealing with citizen disputes and matters brought by the King of England against his subjects who had dis- turbed the King’s peace. The former actions were considered civil and the latter were considered criminal. These courts were always secular and at least from the 11th century on relied upon juries to hear the evidence and make a decision concerning the questions of fact raised by the parties to the litigation. Following the American Revolution in the United States, another division of courts occurred with the creation of the federal court system. The U.S. Constitution established the judiciary as a completely independent branch of the government. 2 Further, it established that the jurisdiction of the court would be cases and controversies arising in law and equity, clearly merging the two courts. Judicial administration was an important part of the Bill of Rights, the first ten amendments to the Federal Constitution which were appended to the originally ratified constitution. Of the ten amendments, five dealt explicitly with the courts, with the fourth, fifth, sixth, and eighth dealing with criminal matters as opposed to suits in common law. Types of Courts of Law: Civil and Criminal The constitutional distinction between common-law suits and criminal mat- ters reflected an increasing appreciation of differences between civil and criminal cases. This distinction has become increasingly codified, driven in large part because of the criminal matters included within the first ten amendments of the U.S. Constitution. Initially, the rights enumerated in the U.S. Constitution to the defendant in criminal matters, such as the right to counsel, the right to not testify, the right to be secure from unreasonable ©1997 CRC Press LLC searches and seizures, and the right to confront witnesses, applied only to the federal criminal courts. Although state constitutions often contained language similar to that in the U.S. Constitution, the U.S. Constitution’s guarantee of rights could not be applied to the states. Only those rights found in the individual state constitutions as interpreted by the individual state courts were applicable to criminal actions in state court. However, the 14th amendment to the U.S. Constitution asserted that the states could not deny due process to their citizens. In Mapp v. Ohio, 3 decided in 1961, the U.S. Supreme Court held that the right against unreasonable searches and seizures was applicable to the states and that illegally obtained evidence would be excluded from the trial. The court arrived at this conclusion because “due process” was interpreted to include exclusion of illegally seized evidence, and the 14th amendment made this right applicable to the states. In Miranda v. Arizona, 4 the court held that the accused must be advised of the right against self-incrimination, the right to assistance of counsel, and the right to have counsel provided by the state if the defendant is indigent. These defendant rights have had a significant impact upon the introduc- tion of scientific evidence in criminal cases. Indeed, the collection of physical evidence is a seizure and therefore if the physical evidence belongs to the defendant or is contained within property controlled by the defendant, then either consent must be obtained from the defendant or a properly executed search warrant must be obtained before the item may be used as the basis of evidence. Other matters which impact the introduction of scientific evidence include the concept of the “Fruit of the Poisonous Tree” first developed in Wong Sun v. United States. 5 Basically, the courts have held that illegally obtained information, whether by illegal interrogations, illegal searches and seizures, or illegal arrests which then results in the finding of legally obtained evidence, shall result in the exclusion of the derivative evidence. In civil matters, those involving the potential loss by the defendant of property but not of liberty or life, the requirements for due process have been interpreted much more loosely. Thus in civil litigation, the requirements of unanimous jury verdicts, right to confront witnesses, exclusion of tainted evidence, and myriad other matters are not applicable. Coroners and their courts are a fourth distinct court system in the United States, or at least in some parts of the United States. The coroner represents the vestige of Roman law which was introduced to England during the Nor- man period. The coroner is a judicial officer, operating from the adminis- trative branch, who applies an inquisitional system of justice which is the norm in French-, Spanish-, and German-speaking countries, but which is unusual in English-speaking ones. Because of its non-adversarial, inquisi- tional nature, coroner’s courts lack evidentiary rules. ©1997 CRC Press LLC There is one other inquisitional institution other than the coroner and that is the grand jury. The grand jury must return an indictment before federal criminal charges may be brought, and in most state courts, the grand jury must return an indictment for capital crimes. Lesser charges generally do not require the grand jury to indict before a prosecution may be brought. The grand jury operates under the judicial branch of government, but is inquisitional. Thus there are no evidentiary rules for the grand jury as well. Evidence — Testamentary and Demonstrative or Physical Having reviewed the distinctions between various courts and civil and crim- inal law, we may now turn our attention to evidence in general. Evidence is anything perceptible to the five senses when submitted to court or jury, if competent. 6 Historically, and generally, the jury has heard evidence as opposed to seeing, touching, smelling, or tasting. However, all senses may be employed. Thus substantive items may become evidence, although gen- erally most information is conveyed by the testimony of witnesses, and in the case of criminal trials, this testimony must be live to comply with the confrontational clause of the sixth amendment. Testamentary evidence is what the witness says. Testamentary evidence is absolutely required to prove any contested fact in the trial. A witness must be sworn to tell the truth. Then using nonleading questions, propounded by the side calling the witness, the witness may say what he or she saw, heard, touched, smelled, or tasted. This is called direct testimony. The opposing side may then ask leading questions, ones which contain within the question the expected answer such as, “Isn’t it true that…,” to try to impeach the testimony given in direct testimony. This is called cross-examination. Demonstrative or physical evidence is something which may be seen, heard, touched, smelled, or tasted by the jury itself. It is necessary that the physical evidence be introduced by a person who is presenting testamentary evidence. Physical evidence cannot be introduced without a testamentary witness. Thus physical evidence is always derivative of some sort of testimony. Evidence is presented by direct examination by the attorney calling the witness. Direct examination must include questions which do not supply the answer to question in the question. “What, if anything, did you do next?” is a perfect nonleading question to ask during direct examination. “Did you pick up the gun?” is an example of an impermissible leading question on direct. Following direct examination, the attorney for the other party may ask questions on cross-examination. During cross-examination leading ques- tions are permissible and indeed are expected. There is a limit to leading ©1997 CRC Press LLC questions, however. “Have you stopped beating your spouse?” is just such an impermissible question. If the witness had not been beating his or her spouse, both yes and no are improper answers. Generally, the attorney calling the witness will object to this sort of question. It is also proper for the witness to give a nonresponsive answer by saying, “I have never beaten my spouse.” Good attorneys are adept at cloaking the spouse beating question in difficult- to-recognize formats. Relevance, Materiality, Credibility, Competence Before evidence may be presented to the trier of fact, a threshold matter concerns the relevance, materiality, credibility, and competence of the evi- dence. These are threshold matters which the judge may be asked to rule upon either as pretrial motions or by objection after the witness is called. As with everything having to do with trials, rights are not self-executing. A party may call an incompetent, incredible, immaterial, and irrelevant witness and if the other side fails to object by motion or by timely objection, then the evidence will come in. In the U.S. system of justice, the judge generally is not expected to limit testimony or the introduction of physical evidence unless asked. Relevance and materiality have to do with whether the testimony or physical evidence shall assist the trier of fact to make a decision concerning the issues in the litigation. These questions are always dependent upon the facts and circumstances of a particular trial. To explain, let us use as an example a criminal trial where the state is bringing charges of murder. The defendant has denied all of the elements of the murder charge. The state wishes to call a witness who will testify concerning the television programs which were on a certain channel on the day of the murder. On its face, it seems difficult to understand how telling the jury what was on television is relevant to the elements of murder. Thus the defense may object to the testimony on the grounds that it is irrelevant and immaterial to any issues in the trial. It is then up to the state to explain to the judge that subsequent witnesses will show that the victim was in the habit of watching a certain program, and at all other times had the television set off, and that when the body was found, the television was on — this then having an important implication as to the time of the attack which was at issue. The judge may admit the evidence presented by the first witness, pending the second testi- mony making the television testimony relevant. The judge may make the state call the habit witness first and then call the television witness. If the judge allows the testimony of the first witness and then subsequent testimony fails to make the television witness’s testimony relevant and material, then the testimony may be stricken from the record and the jury instructed to disregard any of the testimony. ©1997 CRC Press LLC The matters of credibility and competence have to do with more matters of degree than of inadmissibility in modern courts. Historically, only adult males were considered competent to testify, hence the word testify is derived from the same root as testes, the male reproductive organs. Absence of testes made for incompetence to testify. In an effort to present the trier of fact with as much relevant and material information as possible, the threshold question as to credibility and competence usually arises in fact witness testimony in the case of very young children or the severely retarded or if the witness was not in a position to perceive anything concerning the place and event at issue. Relevance and materiality, and to a lesser extent credibility and compe- tence, are threshold matters and must be established by answers to prelimi- nary questions of the witness. These are predicate questions which establish the relevance and materiality and credibility and competence of the witness. For instance, asking a witness his or her name, and then asking, “Did you see the defendant strike Mr. Jones?”, should have the other side objecting that the question is improper because it lacks the proper predicate. These predi- cate questions must first be asked to show that the witness can see, that the witness was at the place of the event at the time of the event, and that the witness knew who Mr. Jones was or came to know his name. All of these questions are required to lay the predicate for the question concerning the battery which the witness observed. On this question of competence to testify, or of matters of materiality as well, the attorney opposing the introduction of the evidence may ask for voir dire of the witness out of the presence of the jury. The phrase means “speak the truth” and is preliminary questioning whereby an inquiry may be made into any of the objections to allowing the witness to testify. At that time, the opposing attorney can move the court to exclude the witness. Types of Testamentary Witnesses Fact Witnesses Generally, witnesses may only testify concerning what they themselves expe- rienced by the operation of their five senses and their current recollection. Testimony concerning their opinion of what they observed, or more impos- sible their opinion based upon the observations of others, is not allowed. Clearly there is no bright line between opinion and observation. Indeed, even the use of the term opinion may not mean the testimony is opinion testimony. For instance, asking the question, “In your opinion was it raining at that time, if you could tell?”, is actually a question which calls for direct observation. ©1997 CRC Press LLC The question, although unartful, is permissible from a fact witness and should be allowed by the judge. Again, in trial, any question is allowable if not objected to by the other side. Generally, a question of a fact witness containing the word opinion will prompt an objection by the other side. The distinction between fact and opinion may become even more obscure in questions dealing with more complex observations. The question, “Was the car moving or not?”, would seem to be completely proper question of a fact witness. However, “How fast was the car moving, if it was moving?”, is a closer question, although most courts have recognized that estimating speed from direct observation of movement over time seems to be a direct observation of the moving vehicle. On the other hand, estimating the speed of a vehicle from the length of the skid marks would seem clearly to be testimony which requires an expert. Expert Witnesses An expert is a person who by training, education, experience, or a combina- tion is able to assist the trier of fact by offering opinion testimony concerning matters in dispute. The same rules of materiality and relevance apply to the expert witness as to the fact witness. Many times a person who is involved in testifying concerning scientific evidence is both a fact and expert witness. Some of the information may have been obtained by direct observation and then from direct observation opin- ion testimony is made. For example, if an investigator actually measured the length of the skid marks in an accident, he or she may testify to the length, obviously after the proper predicate questions are asked. At this time, the attorney may want to ask the question as to how fast the car was traveling based upon the length of the skid mark. This is clearly expert testimony which may be given only by an expert. The preliminary matters which must be obtained from an expert witness are the training, education, and experience that the expert has. With expe- rienced and well-trained experts, the other side may concede that the expert is an expert, thereby saving the court and jury’s time, as well as, of course, depriving them of learning how qualified the expert is. Generally, the side calling the expert will request to be allowed to go into the expert’s back- ground, and at some point the judge will be asked to rule whether the witness is an expert. If the judge decides that the witness is an expert, then questions which are relevant and material to the issues before the court and which are within the expertise of the witness are allowed which require an opinion, and which are based upon observations which were not directly made by the witness, but are presented as hypothetical questions. ©1997 CRC Press LLC Hypothetical Questions Experts in the field of scientific evidence often did not make the observa- tions which are required to arrive at opinions concerning matters which are relevant and material to the trier of fact. Let us return to the motor vehicle collision again. One of the parties has called an expert in accident reconstruction who, if allowed, will testify that the speed of the automobile involved was 80 miles per hour based upon the skid mark length and an examination of photographs taken of the vehicle following the crash. The expert did not measure the skid marks nor make the photographs. The predicate questions here will concern the reliability of the science of kinetics and an explanation that if one knows the mass of a vehicle, the coefficient of friction which is created at the time of locking up the vehicles tires on the type of roadway involved, and the collision velocity at the time of contact which can be estimated from the static deformation of the vehicle, then the speed at the moment the brakes were applied may be estimated. All of the above being established, the witness would also be asked if the amount of crush damage may be ascertained from examination of photo- graphs and if this is routinely done by experts in the field. Assuming the photographs have been properly introduced by another witness, then the expert may be properly asked a hypothetical question. The hypothetical question should track the evidence which has been or will be presented at trial by the fact witnesses concerning the road conditions, the road surface condition, the deviation from horizontal of the road, the temperature of the air, the tire treads, the brake examination, the length of the skid marks, the weight of the vehicle at the time of the accident, and any other matters which the expert feels relevant to his or her analysis. These facts used in the hypothetical must have been proved or will have to be proved prior to the conclusion of the attorney’s part of the trial. If they are not, then the opinion testimony of the expert is subject to be stricken and the jury instructed to disregard it. Cross-examination of an expert witness will often include hypothetical questions as well. However, the hypothetical presented by the cross-exam- ining attorney will contain the facts that the attorney feels he or she may be able to prove. Again, hypothetical should not contain facts which have not or will not be proved. However, in the case of cross-examination questions, most judges allow greater leeway as to whether or not the factual elements must be proved. This often leads to confusion of the witness and the jury, which can be a legitimate object of cross-examination. ©1997 CRC Press LLC Physical or Demonstrative Evidence A fact witness may introduce into evidence physical objects which are mate- rial, relevant, credible, and competent. In criminal trials such items as the weapon, or the drugs, or the bloody clothing are all subject to becoming physical evidence. The rules are essentially the same for physical as for tes- tamentary evidence. However, physical evidence must meet materiality and relevance tests in its own way. Particularly with an item which is fungible, meaning a thing which cannot be differentiated upon physical characteristics alone, there must be predicate questions which link it explicitly with the events and issues concerning it in the trial. This process is usually thought of as “chain of custody” or “chain of evidence”. It is but one way, and the most commonly utilized way, of intro- ducing physical evidence or of introducing results of testing done on physical evidence. Fact witnesses will have to be called who can show that there was an unbroken chain from the location of the item when it was first obtained, through whatever handling it received, until it was tested or was introduced as evidence or both. Breaking the chain, being unable to trace the location and condition, of the material generally will result in the testing and/or the introduction into evidence being disallowed. Again, the process is one of determining materiality and relevance. Obviously if there is more than a remote possibility that the item in question is not related to the issues in question, then it is immaterial and irrelevant. Again, the process may entail pretrial motions or voir dire to determine these threshold questions of admis- sibility. One special type of physical evidence often used in criminal as well as in civil trials is photographic and videographic evidence. In cases where there is injury, and where the photographs show those injuries, then another test as well as those previously described is required. The materiality, relevance, and competence questions are generally handled by asking an eyewitness whether the photographs “truly” and accurately display the scene, body, car, or whatever as it was at the time of the crime, accident, event, or whatever. The next question is, “Would these photographs aid you in showing to the jury the scene, body, etc. which you witnessed?” These are leading questions, but generally allowed in direct. The first question satisfies competence; the second satisfies relevance. They may be asked in the alternative and they are no longer leading as in, “Do or do not these photographs …?” Most juris- dictions have a third test to be considered by the judge. This is whether the photographs’ inflammatory value exceeds their probative value. There is always a fear that in the case of injured persons that the shocking nature of ©1997 CRC Press LLC injuries will cause such an emotional state in the jury that it will be incapable of rationally deciding the issues. With the current state of motion picture and television depictions of violence, these concerns have become lessened. Hearsay Finally, a word about hearsay. As a general rule, hearsay is inadmissible. Thus a question which will elicit hearsay is improper. The question, “And then what if anything did Mr. Smith say?”, is on its face improper and will almost always prompt an objection from the attorney on the other side. The point of this exercise being that if Mr. Smith has something to say which is relevant and material, as well as competent, then Mr. Smith should be sworn in as a witness and asked direct questions and then be available for cross examina- tion. However, there are myriad exceptions to the hearsay rule. These are exceptions which because of convenience or need make the hearsay evidence necessary for the proper administration of justice. The most common exception to the hearsay rule is the confession in criminal cases. A confession is hearsay. It was not made in court, after the witness had been sworn, with the opportunity for direct and cross-examina- tion. Thus it is inadmissible, except if it is within an exception to the hearsay rule. Such an exception is that admissions against penal interest are excep- tions to the hearsay rule. Thus, if the person has said things which implicate him in a crime, then they are admissible hearsay. There are at least 40 exceptions to the hearsay rule. Thus although hearsay is not allowable by the general rule, often an exception can be found which allows hearsay to come into evidence. Competence A special test for competence is required with scientific evidence. The ques- tion is whether the science or the scientific tests employed are of such a level of validity as to be allowed into evidence. Historically the test was whether the science was “generally accepted” as being valid. This test of “general acceptance” was first enunciated in 1923 in Frye v. United States of America, a criminal case in which the United States wished to introduce polygraph evidence. 7 Evidence of validity included published reports in peer-reviewed journals. In rapidly advancing fields such as so-called “DNA testing”, the delay in publication often threatened to limit truly valid science from trial. The so-called “Frye test,” at least in federal court, has been changed allowing rapidly advancing science to be introduced. In Daubert v. Merrell Dow Phar- maceuticals, the U.S. Supreme Court introduced a four-part test to replace Frye: ©1997 CRC Press LLC [...]... Press, Westbury, NY, 1995 2 United States Constitution, Article III 3 Mapp v Ohio, 36 7 US 6 43 (1961) 4 5 6 7 8 Miranda v Arizona, 38 4 U.S 436 (1966) Wong Sun v United States, 37 1 U.S 471 (19 63) In re: Fischers’ Estate, 47 Idaho 668 Frye v United States, 2 93 Fed 10 13, 1014 (DC Cir 19 23) Daubert v Merrell Dow Pharmaceuticals, 1 13 S.Ct 2786 (19 93) ©1997 CRC Press LLC Legal Medicine and Jurisprudence 6 CYRIL... relations, J Pub L., 3: 30 4 30 6, 1954 3 An Act to Amend the Law Relating to Coroners, Geo C., 59: 16–17, 1926 4 The New Republic, Feb 13: 15, 1971 5 Cobbs vs Grant, Cal Rptr., 104: 505, 19 73, and Canterbury vs Spence, 404: 772, 1972 6 New Republic, 164: 15, 1971 ©1997 CRC Press LLC 7 M’Naughten’s Case, Eng Rep., 8: 718, 18 43 8 Robinson vs California, 37 0 U.S 660 (1961), and Powell vs Texas, 39 2 U.S 514 (1967)... unrecognizable body Forensic odontology takes the general identification made by the forensic anthropologist, and specifies exactly who the body belongs to This specialty comes into play primarily with burn victims and other bodies whose physical characteristics have been significantly altered ©1997 CRC Press LLC Forensic toxicology deals with detecting and interpreting organic and toxic materials A forensic toxicologist... they are asked The witness should listen to each question asked and make certain that the opposing attorney has had the opportunity to object to the question prior to answering Failure to do so will generally lead to an admonition from the judge and at worst could lead to a mistrial, if impermissible information is presented to the jury Objections may be made to answers as well as questions The most... surgical complications It is easy to see how this situation would also apply to malpractice deaths To recap, the forensic pathologist integrates all the information concerning a death into his findings: toxicology reports, forensic odontology and anthropology reports, circumstances at the scene of death, etc He then goes beyond merely determining the medical cause of death to a determination of the time,... modern forensic pathology dates back to the Renaissance in Europe and at least two centuries in England To qualify to take the national certification examination, a physician must meet the following requirements: 1 Undergo standard training in anatomic pathology 2 Complete a one-year residency at one of 25 recognized training centers in forensic pathology 3 While at such a center, perform at least 30 0 autopsies... CRC Press LLC Forensic Pathology RONALD K WRIGHT WILLIAM G ECKERT 7 Forensic pathology is probably the oldest branch of the forensic sciences, and, indeed, until the first quarter of the twentieth century, virtually all forensic sciences were a branch of the medical examination of forensic problems Since then, the explosive expansion of criminalistic techniques has taken the forensic sciences in numerous... Britain, more forensic pathology is performed by general pathologists than by full-time forensic pathologists Role of the Forensic Pathologist Leaving aside clinical forensic medicine for the moment, a primary function provided by most forensic pathologists is the examination of the dead body Indeed, currently in the United States it is estimated that the number of forensic to non -forensic autopsies is... a toxicology report, a different conclusion as to the cause of death of several miners would have been reached, since the blood of at least five contained lethal levels of carbon monoxide Within such a wide range of expertise the forensic toxicologist assumes the role of monitoring our environment and technology and educating the public on these areas To date, of all the forensic specialties only forensic. .. survived whom An integral step in an investigation to determine answers to questions such as these is a visit to the scene of the event The forensic pathologist makes such visits in order to evaluate the death in the overall context of the victim’s milieu Situations at a scene that may seem inconsequential to others often provide crucial information to the forensic pathologist, and inconsistencies that . judge in U.S. courts, is to see that the issues to be tried are as limited as possible, to preside over the trial, to limit evidence to the issues that are to be tried, and to instruct the jury on. should listen to each question asked and make certain that the opposing attorney has had the opportunity to object to the question prior to answering. Failure to do so will generally lead to an admonition. States Constitution, Article III. 3. Mapp v. Ohio, 36 7 US 6 43 (1961). 4. Miranda v. Arizona, 38 4 U.S. 436 (1966). 5. Wong Sun v. United States, 37 1 U.S. 471 (19 63) . 6. In re: Fischers’ Estate,