Category Archives: Expert Opinions

Crime Scene Video

Crime Scene Video-Exporting VS Screen Capture from CCTV Systems

There are more digital video file varieties in surveillance video than any other form of digital video. The reason for this is because each manufacturer programs their own proprietary digital video format in order to keep their CCTV video recordings secure. When a crime has been committed and caught on video, the video forensic expert must decide the best way to acquire that proprietary video so that it can be used as evidence in court.

Most CCTV systems have export features. Video and images can be removed from the CCTV system easily and securely.  This exporting feature is not always the best method from a forensic perspective. Exporting video from the CCTV surveillance system often compresses the digital video file too much for the video forensic expert to enhance. In order to enhance a portion of surveillance video the video forensic expert must start with the highest quality possible.

I have found through experimenting that screen capture programs like Camtasia can create digital video exhibits of much higher quality than many CCTV surveillance systems. Lately, for every case I investigate that requires digital video enhancement or clarification, I use both the CCTV system export (usually an AVI file format) as well as a screen capture from Camtasia to compare the quality.

Most law enforcement authorities use a screen capture method because it is faster at the scene of the crime to capture the video evidence instead of exporting.

I often realize that the compression that the proprietary player exports is not suitable for forensic examination and clarification.  The system export resolution and bit rate are too low for a video forensic enhancement starting point.

On the other hand, I can set my screen capture specifications much higher for resolution and bit rate when recording the same series of events on the CCTV system video monitor.  Camtasia has an HD option for exporting that dramatically increases the bit rate and data rate providing a much better starting point for enhancement and clarification. Because I have both the export and screen capture videos, there is no doubt about chain of custody and process documentation for my forensic report.

I will be creating a series of videos in the near future using Adobe Premiere Pro for video enhancement and clarification using both methods to further exemplify the necessity for both methods of evidence gathering.

School and Summer Camp Liability Expert

School and Summer Camp Liability

As we approach summer, many children look forward to graduation or summer camp, or are excited about building memories and finishing the school year with exciting field trips and proms. Few schools and camps, however, consider the liability that might stem from relaxed rules, “summer fever,” and hastily organized activities. Many children are injured at this time of year when rules are relaxed and appropriate supervision is not always provided.

Graduation activities — all-night lock-in parties, in particular — present several dangers. All-night parties under school supervision are popular because they reduce the risk of alcohol and drug abuse by students who might attend other, nonsupervised events. But they expose students to a new danger: sleep deprivation, graduation’s night silent killer and the second biggest killer on our highways. Typically, event planners keep high school graduates, who have been in school since early morning, entertained from the beginning of the party until the next morning with a variety of activities. In the morning, students leave unsupervised and in a condition that research shows is similar to alcohol or drug intoxication — resulting in car accidents and sadly death. Yet, based on data I gathered through a telephone survey of more than 300 high schools across the United States, those who plan all-night graduation parties generally do not consider fatigue and sleep deprivation as potential risks.

A few easy and effective precautions can protect schools from lawsuits. Transporting students in school buses to the event and back home in the morning can save lives. Even if transportation is provided, adopting clear policies and procedures to protect students from driving while sleep-deprived is equally as important. These policies should specify that under no circumstances will any student, staff member, or parent chaperone be allowed to drive after an all-night graduation party. Other transportation options must be arranged. Schools have a duty to protect students from harm, and no reasonable educator would allow an intoxicated student to get behind the wheel of a car. Why allow a sleep-deprived student to do the same?

Field trips                                                                             

The same logic follows when it comes to end-of-the-school-year field trips and other activities, as well as half days and irregular schedules. Unfortunately, there are numerous cases involving field trips that resulted in drowning deaths, sexual assault, hazing, and bullying — all resulting from the lack of organization, clear rules, too few chaperones, or inadequate supervision of students.  Special attention and planning needs to take place for students that have a demonstrated a need for extra supervision in the past or need one-on-one supervision. Teachers in charge need to maintain high standards of supervision for all students during field trips. Some considerations include:

  • The age of the students
  • Whether a student has a disability that requires additional supervision
  • The number of adults needed to keep an eye on all the students
  • The uniqueness of the location that might require additional supervision
  • Safety hazards at the site, such as a river, cliff, or highway

All of these issues should be considered and addressed before the administration approves a trip and sends notices home to parents. Planning, clear rules and policies, and appropriate supervision can save a student’s life and prevent a costly legal battle for the school if a child is injured while participating in the activity.

Summer camps

Parents should keep liability issues in mind when researching summer camps. Overall, summer camp can be a valuable and delightful opportunity for any child, as it is a place to reach out and try new things, meet new people, and develop as a person. On the other hand, camps can be full of hidden liability traps; sleep-away nights, horseback riding, archery, rifles, rope swings — all involving children who are supposed to be supervised by trained adults (in some circumstances, college students), Many of these types of activities are accidents waiting to happen. Cases involving campers being injured or sexually abused as a result of poor supervision and staff training are not unusual.

To avoid exposure to a litigation-conscious population, summer camps have instituted the practice of making campers and families sign all-inclusive liability waivers. When well-written waivers have been in place, many verdicts have favored camps and other agencies that supervise children’s programs because parents released them from liability. If a camp or agency institutes clear policies, follows procedures, and does everything right, it is highly unlikely that a parent would win an injury lawsuit.

All-inclusive waivers, however, do not always protect a camp. A waiver is not valid if an injury can be attributed to the camp having breached a standard of care or if it was careless or negligent about supervision. If, for instance, the camp or agency didn’t maintain its playground equipment properly and a child was injured, the camp may be liable, invalidating the all-inclusive waiver. Depending on the specific issue of supervision (or lack of it), an all-inclusive waiver might not protect the camp.

10 considerations

Numerous elements should be reviewed when examining cases that involve injury at a school-sponsored event or summer camp. In no particular order, here are 10 key considerations:

  1. What risk-management procedures does the school or camp have in place?
  2. How are staff, counselors, and volunteers screened and selected? Are criminal background checks performed prior to supervision — even for summer jobs?
  3. How are volunteers trained before they supervise a school- or camp-sponsored trip?
  4. What kind of discipline code is followed? Is it enforced? By whom?
  5. Are yelling, bullying, harassment, or physical force tolerated? How are incidents of violence and abuse handled?
  6. Do students or campers know whom they can talk with and what to do if they feel unsafe or harassed?
  7. Are appropriate procedures in place to prevent teachers, counselors, and volunteers from being alone, one-on-one, with children?
  8. Are at least two counselors or adults present in each cabin at a sleep-away camp?
  9. On class trips, is there adequate supervision for the size of the group? Are there, for example, at least two staff members or volunteers for class trips of eight or ten students?
  10. Are age groups reasonably established and kept separate for activities and sleeping?

Meticulous planning will not necessarily prevent lawsuits in case of an injury, but it will keep children safer and could help a school, camp, or agency avoid liability. School and camp administrators should instruct their staff to consider all the possible dangers that might cause injury to a child at an all-night graduation party, a field day activity on school grounds, a day or overnight trip, or other end-of-the-year or summer activity. Make a list of how each of these possible dangers can be avoided. Looking at the possible unfortunate outcomes of injury and planning for the protection of children is the duty of those responsible for children in schools and camps.

Robocalls

The Process of Voice Identification

As an audio forensic expert, one of my day-today activities is voice identification. There is a misunderstanding about voice identification that has confused our courts in the United States creating the perception that voice identification testing is not a reliable science. In the following article, I hope to clear up the misconception of voice identification testing as well as communicate some ‘outside the box’ testing techniques that have successfully solved cases where other forms of identification were not possible.

Our court system is full of digital audio recordings that are evidence in criminal proceedings as well as civil litigation. As an audio forensic expert, I have testified in many cases in the United States and worked on cases around the world that involve voice identification. Voice identification is a viable science that involves both science and art. By art I mean discretion of the audio forensic expert to use ‘outside the box’ investigation techniques to help move along due process.

Some of the time my ‘outside the box’ voice identification testing is a matter of life and death. When a company receives a threatening voice mail recording and has an idea of who made that recording, they will call an audio forensic expert like myself and ask for our third party, unbiased opinion. Because I have no stake in the outcome, I can proceed with the untraditional testing in order to deliver my opinion of the probability of the suspect being the one who left the threatening voice mail message.

This serves two purposes. First it helps the organization know that professionals are looking into the origin of the threatening voice mail message. This is comforting to employees especially the employee who received the voice mail message. Secondly, it helps with the conviction process. In other words, when I deliver an opinion, I use a percentage of probability in my initial verbal report. The organization then takes that professional test result to the accused and some of the time they admit or confess and other times they agree or consent to cooperating with the investigative team to create an exact exemplar for more in-depth voice identification testing.

The starting point for any voice identification test is to be able to clearly hear the voice in question that is to be identified. Part of this initial process is to remove any background noise in the audio recording that is unnecessary and distracting to the expert’s sound perception. This noise removal is a process like peeling an onion. The goal for the audio forensic expert is to create custom filtering that increases the volume of the voice in question and remove any unnecessary background noise. This noise reduction filtering process is done a step-by-step, incrementally fashion.. In other words, part of the background noise is removed then the volume of the voice in question is increased. This step-by-step process is the discretion of the voice identification expert. The reason why the expert makes decisions  one at a time is because every recording is different.

When conducting a voice identification test, an audio forensic expert looks for spectrums that match the recording in question against the exemplar. An exemplar is a comparison recording that a forensic expert creates of the voice in question for comparison purposes. Even more important are the words themselves. The way the words are pronounced, the pacing of the words pronounced, the space between the words, the articulation of the words and the idiolect of the speaking word delivery style—all are indicia of a voice.

No two human voices are the same ,just like no two fingerprints are the same. Regardless of attempted voice disguise cover up, a trained forensic expert can identify a voice and compare to another to determine identification.

With experience, a trained audio forensic expert can use voice identification skills in a variety of ways and help uncover the truth behind audio recordings.

For example, in the case of the ‘who cried for help’ question around the Trayvon Martin killing in People V. George Zimmerman, there are only screams, not words that an audio forensic expert can compare and identify to the best of their ability. I have formed an opinion about who I believe cried for help before Trayvon Martin was killed by George Zimmerman and have written several blog posts about my opinion. I have also appeared on national television discussing my process and opinions. This is ‘outside the box’ voice identification testing. Is it reliable? In my humble opinion the answer is yes.

Regardless of the type of voice identification testing, the second step, once the recording is as clear as possible, is to create a comparison file that includes back-to-back samples of speech from the accused (exemplar) as well as the evidence or threatening recording. I did this in the case of George Zimmerman before I formed my opinion. Using the example of the threatening voice mail message, each telephone message included two voices. The goal is to determine what percentage of possibility that both voices came from the same person.

During the investigation, I separate the voices – the suspect and the evidence – and create a new audio file called ‘comparison’. That way I can critically listen to all voices back to back in order to determine if any of the voices were identical or at least had similar characteristics.

Once I complete this back-to-back assembly process, I create work notes listing all the similarities as well as differences observed during the critical listening phase of the voice identification testing.

These notes help me provide my opinion and create a report explaining my processes when the voice identification testing is complete.

I also use spectrum analysis and sonograms to help arrive at a conclusion with the identification process. Often I print out the display of these two electronic measurement devices and include these images in my report.

One thing I have learned over the 29+ years as an audio forensic expert: keep it simple. Judges and juries like an uncomplicated decision from a qualified forensic examiner. They become frustrated when they have to interpret new information they have never heard of or are not familiar with.

Voice identification is both an art and a science. As a voice identification expert, I use my talent, skill and ability in every case I am assigned to. The science is acceptable in court and the art is the ability to adapt every case to scientific standards.

http://www.youtube.com/watch?v=73tPKeKddfE

Supervision of Children - School and Agency Negligence

Supervision of Children: School and Agency Negligence

Many of the cases for which I provide consultation and expert witness testimony involve the question of whether a school or agency provided appropriate supervision when someone under its care was injured. The question asked by a child safety and supervision expert in such cases is, “Did the school or agency, through its administration and/or other employees, act reasonably and within the standard of care in accordance with the customs and practices of the field?” Lack of or inadequate supervision is the most common allegation of negligence. It is estimated that in cases involving programmatic situations (i.e., where standardized procedures exist), approximately 80 percent of plaintiffs’ allegations involve supervision. My experience in working on such cases reinforces this statistic.

Lack of supervision itself may not necessarily create liability; it must be shown that lack of supervision is the proximate cause of the injury. For the plaintiff to recover, the defendant must also have a duty to supervise the plaintiff. A key element here is the distinction between a duty to render specific supervision and a duty to provide general supervision.

Specific Supervision

Specific supervision is required when a person is involved in activities in settings with obvious hazards, or is incapable of protecting himself from harm in these settings. The type of supervision required depends on the activity and age of the children. A good example would be supervision of children who cross a highway to reach a school or a bus stop. In this case, there would be a duty to supervise, and that duty would be even stronger to supervise 5-year-old children as opposed to high school students.

Another situation in which specific supervision would be required is when participant behaviors indicate a need for it. Such an example would be when the teacher or supervisor has been warned about the “propensity” of a child to behave in a manner that is either self-injurious or dangerous to others. The combination of a child who is known to behave in a dangerous way and environmental hazards that pose a threat of injury mandate specific supervision.

Specific supervision is most often thought of in the instructional mode. From a legal perspective, instruction is given so that the student can gain knowledge of the activity, understand the activity in terms of one’s own capabilities, and appreciate the potential for injury before assuming the inherent risks of the activity. As the participant gains in knowledge, understanding, and appreciation, the degree of specific supervision required is gradually reduced as the participant is provided with transitional supervision and then general supervision.

The individual defines the need for specific supervision. Specific supervision is not a function of the activity, but of the person who participates in it. Some people talk about “high-risk” activities or “hazardous” activities. Courts have not held any activity except boxing inherently dangerous. Rather, the key lies in the person, how she participates in the activity, and how she should be supervised. Think of “people hazards” rather than “activity hazards.” The determinant of likelihood of injury is directly related to the participant’s skill capacity; physical and mental condition to do the activity; and knowledge, understanding, and appreciation of the activity itself. If, for instance, physical disability or lack of mental capacity diminishes a person’s ability to perform an activity, then specific supervision is required.

General Supervision

Children transitioning from one activity to another in school or at a summer camp do not require specific supervision if there are no obvious hazards present. As long as the supervisor-to-child ratio is reasonable and that supervisors in the area are aware, listening and responding when necessary, then the general supervision standard of care is met.

General supervision has two dimensions — individual-oriented supervision in an activity, and group–behavior-oriented supervision in a facility or other location. When engaged in individual-oriented supervision, the supervisor is focused on the child’s manner of engaging in the activity. For example, a teacher in a shop class watches to ensure that students properly use the equipment. In contrast, someone assigned to group-behavior supervision in a facility or an area (e.g., a cafeteria or an outdoor recreation area) watches the behaviors of children and dangerous conditions.

Almost all playground cases allege lack of supervision; in most cases, however, general supervision is all that is required. While a school or agency is not an insurer of safety, there must be supervision when children are on the playground during times when the school or agency is in charge, such as during recess. The fact that each child is not personally supervised every moment of each school day does not constitute fault, nor do spontaneous or planed acts of violence by children on school grounds create liability if the area is well supervised. Constant and undeviating supervision would be prohibitive and, probably, impossible.

Supervisors, however, should be alert for prohibited or dangerous activity that prompts a need to transition from general supervision to specific supervision. A playground monitor, for instance, provides general supervision at recess, watching or listening for anything that might indicate that a child could cause harm to himself or another person. If the monitor witnesses a child jumping from the top of a slide, the monitor must move from general to specific supervision. A reasonable supervisor would know that this is a dangerous situation that could result in injury — necessitating the provision of specific supervision. If supervisor calls out to the child and quickly goes to the area to intervene so that the child discontinues the behavior, the supervisor has acted appropriately under the circumstances to keep the child safe.

Numerous Variables

Recent cases for which we have provided consultation demonstrate that though a school or agency may have appropriate safety procedures in place, a child can, nonetheless, become injured. In such case, a summer camp met all the standards with regard to child supervision; yet when a child threw a stick to the ground, it bounced up and struck another child in the eye.

In this case, camp staff had previously seen children picking up sticks and instructed them not to play with sticks, as part of their safety lessons. The staff-to-camper ratio exceeded the standard and, at the time, the staff was providing appropriate supervision. The children were moving from one location to another, making general supervision the standard. Camp counselors watched the children carefully and were close enough to intervene, if necessary. Suddenly, the child picked up a stick. As soon as he noticed that a counselor was watching him, he threw the stick down. The stick bounced off the ground and struck the other child.

After a review and analysis of the facts and circumstances, my rendered opinion was that the camp met the standard of care in accordance with the customs and practices of the field. The type of supervision and number of counselors present were adequate for the circumstances. The spontaneous behavior of the child who picked up the stick was not foreseeable, and the fact that a staff member watched this action constituted appropriate supervision in the moment. Knowing that he was being watched, the child threw down the stick without warning.

Numerous variables are involved in determining whether a school or agency breached a duty to supervise.  I can help plaintiffs and defendants understand how these variables may influence a determination of liability.

On Being an Effective Expert or How to Help the Jury do Their Job!

Being an effective expert means “Never forgetting that your job is to help the jury do their job.”  Even the Rules of Evidence recognize that experts help the jury, and helping the jury is what testifying as an expert is all about.

Several years ago, I was fortunate enough to hear Judge Hiller Zobel speak at the SEAK conference.  Judge Zobel made some suggestions that are worthy of repeating.  First of all, leave your ego at the door.  Testifying in court is not an opportunity to show the jury how smart you are, nor is it an opportunity to try to impress them with your vocabulary.  Instead, it is a time to provide the jury with helpful analogies that will assist them in understanding the technical material you have mastered.

Think back to the teachers and professors you admired most in high school, college and post-graduate training.  They were the men and women who took the time to think about the information they had to convey and presented the material in a well-organized, interesting and understandable way.  They were not concerned with impressing you with their understanding of the material; they were determined to teach it to you so you could acquire it, and hopefully pass it on to others.

One woman physician I know told me she presents her potential testimony to her pre-teen and teenaged children.  If they don’t understand what she was saying, they give her an “Oh, Ma”, and she goes back to the drawing table.  If they tell her, “Hey, Mom, that’s cool”, she knows she was successful.

Jurors are comprised of people from all walks of life.  Some have been to high school and not gone further, others have been to college.  Either way, there is no typical juror, and there is no “standard education” for jurors.  The one thing that I do know about jurors is that they are very serious about doing their job correctly and take great pride in reaching a fair and well-reasoned decision.  As the testifying expert, you are among those who supplies the answers to some of the questions they have that contribute to that decision.

The one thing that has always impressed me about lawyers is how familiar they are with the details of the case.  Lawyers seem to remember every date and every time.  Jurors notice this too.  When jurors have been polled after trial, many jurors have commented on how well-prepared the lawyers were.  Therefore, if you want to impress the jury, make like a Boy Scout and “Be Prepared.”

Being prepared means being familiar with the facts of the case, and being able to handle questions on cross-examination with facility and aplomb.  If you are not an expert in your field and can’t answer fundamental questions about your discipline, you should not be in court.  You are a charlatan.  This means never representing yourself as an expert in a field in which you are unfamiliar.  A little bit of knowledge is dangerous, and you will get slaughtered by the opposing attorney on cross-examination.

If you think you can “fake it,” you cannot.  It is not the attorney who will be making up the questions, it is the real expert on the other side.

Last year at the forensic sciences meeting, a colleague of mine asked me to quiz one of the toxicologists in his laboratory on the basics of narcotic pharmacology.  I asked him three basic questions, and he could not answer any of them.  The young man is far more adept at working at the laboratory bench than I am, but he does not have a good working knowledge of basic narcotic pharmacology.  Don’t get caught in that trap.  If the expert on the opposing side of the case really knows his/her stuff better than you do, you could be in for a trip to the woodshed.

Another good way to prepare to testify is to prepare the questions you want the attorney to ask you, then think long and hard about how to answer them succinctly.  In the courtroom, less is more.  Try to answer in “sound bites.”  Don’t drag on and on.

Do not be afraid of saying, “I don’t know.”  After all, who among us knows it all.  If you don’t know the answer to a question, say so.  The jury will appreciate your honesty and recognize that the questions you answered, you probably did know what you were saying.  If you make an error–Speak up and correct yourself.  “Excuse me, I think I mis-spoke.  It was 8 am not 8 pm that the accident occurred.”

Please, be yourself.  Don’t try to be someone else.  You’re not Quincy, and you’re not Perry Mason.  Don’t make jokes, respect the sanctity of the courtroom.  If something funny is said or happens, it is okay to laugh.  But the courtroom is no place for levity.  Someone was hurt, died or stands to lose a lot of money.  Be respectful.  Dress neatly and professionally, and do not wear expensive jewelry.  Treat everyone you encounter in the parking lot, the line in front of the metal detector, and in the hallways as politely as possible.  You never know who they are, or if they are going to show up in the jury box while you are on the witness stand.

Finally, I’ll end where I began.  You are in court to help the jury determine the facts at issue.  Do your homework, be prepared, and teach the jury what they need to know.  If you master this simple, yet sophisticated approach, you will make an outstanding contribution to the justice system and can hold your head up high even when the cross-examining attorney is trying to destroy you.  And, I say to you, the measure of a person is grace under pressure, and as Rudyard Kipling said (generically), “If you can keep your head when everyone around you is losing theirs, then you are a man my son!”