Håndskriftseksaminatorer i den digitale tidsalder

Folk skriver mere end nogensinde med deres tastaturer og telefoner, men håndskrevne noter er blevet sjældne. Selv underskrifter er ved at gå ud af mode. De fleste kreditkortkøb kræver dem ikke længere, og hvis de gør det, du kan normalt bare ridse en ud med neglen. Den ældgamle håndskriftskunst er i tilbagegang.

Dette markerer et dybtgående skift i, hvordan vi kommunikerer, men for en gruppe eksperter rejser det også et eksistentielt spørgsmål. Retsmedicinske håndskriftseksaminatorer autentificerer håndskrevne noter og signaturer - eller afslører, at de er falske - ved at analysere karakteristiske træk i vores forfatterskab. Når folk skriver mindre i hånden, bliver håndskriftsundersøgelse irrelevant?

En nylig rapport fra National Institute of Standards and Technology (NIST) antyder, at svaret er nej - hvis feltet ændrer sig for at følge med tiden. Men tiderne ændrer sig på mere end én måde, og faldet i håndskrift er kun en af ​​de udfordringer, som feltet bliver nødt til at regne med.

Hvordan eksperterne gør det

Emily Will er en bestyrelsescertificeret håndskriftseksaminator i privat praksis i North Carolina. Hun har undersøgt underskrifter på utallige checks, testamenter, gerninger og betroelser. Hun har gennemgået journaler for at vurdere, om en læges underskrift kan være tilføjet på et senere tidspunkt end angivet, måske efter en retssag blev anlagt. Hun har også undersøgt længere skriveformer, såsom truende eller chikanerende breve og selvmordsbreve. Hvis det tilsyneladende selvmordsoffer ikke skrev sedlen, politiet kan have et drab på hånden.

For at vurdere om et stykke håndskrift er skrevet af en bestemt person, eksaminatorer har brug for noget at sammenligne det med, så de indsamler skriveprøver, der vides at være fra den pågældende person. Skrifttypen skal være den samme, om en underskrift, kursiv skrift, eller håndtryk. De kendte prøver skal være fra nogenlunde samme tidsperiode som den pågældende håndskrift, fordi vores håndskrift udvikler sig over tid. Og at have flere kendte prøver at sammenligne med er nøglen, da det vil give eksaminatoren mulighed for at overveje variabiliteten i en persons skrivestil.

"Du er ikke en robot, så hver gang du skriver under dit navn, det vil se anderledes ud, " sagde Will. "Det er det, der gør håndskriftsundersøgelse så interessant."

Ikke-professionelle tror måske, at da de fleste mennesker ved, hvordan man fremstiller håndskrift, stort set alle kan undersøge det. De kan antage, at eksperten sammenligner ting som størrelsen, hældning og afstand mellem bogstaverne og forbindelserne mellem dem. Ja, eksaminatorer gør det. Men de ser også ud over disse egenskaber ved at skrive efter subtile tegn på, hvordan skriften blev lavet.

"Sig du vil forfalske en underskrift, " sagde Will. "Du kan muligvis udføre en god faksimile. Men er "O' med uret, når det skal være mod uret? Er der penløfter, hvor der ikke burde være? Når du skriver under dit navn, er det hele muskelhukommelse. Men at forfalske en signatur kræver overvejelser. Pennen sænker farten. Den stopper og starter ." Disse tøven viser sig under et mikroskop som små pøller af blæk.

"Det er ikke så meget, hvordan signaturen ser ud, men hvordan det blev udført, det er vigtigt, " sagde Will.

Her er, hvad Will har med sig i sin go-taske:en guldsmeds lupe, et lille optisk mikroskop og et håndholdt digitalt mikroskop. En lommelygte. Et papirmikrometer, at måle papirets tykkelse. En bærbar og bærbar scanner. Et kamera, der kobles til hendes mikroskoper. "Og ærligt talt, " hun siger, "Jeg bruger min iPhone meget i disse dage."

Wills praksis strækker sig til det bredere felt af "spørgsmålsdokumentundersøgelse, " som involverer at granske et helt dokument for tegn på svindel. I hendes laboratorium, hun har udstyr til at analysere papirer og blæk og se dem under forskellige typer lys. Nogle blæk, der ser identiske ud i dagslys, ser markant anderledes ud under infrarød. Hun identificerer sletninger, ændringer og udslettelse og afslører indrykket skrift - aftryk efterladt på ark papir under den skrevne seddel.

Men det meste af Wills arbejde involverer håndskrift og underskrifter, og der er meget færre af dem i disse dage. Svindel med check-indløsning er langt nede nu, hvor lønsedler og socialsikringschecks er direkte indbetalt. Medical malpractice lawsuits involve fewer signatures since electronic health records have become the norm. Even celebrities have noticed the change. In a 2014 opinion article in The Wall Street Journal, Taylor Swift wrote, "I haven't been asked for an autograph since the invention of the iPhone with a front-facing camera."

Enough handwriting still passes under Will's microscope to keep her in business. Men, hun siger, "If I were a young person starting out today, I might consider cybersecurity."

A Roadmap for Staying Relevant

The field of forensic handwriting examination may have trouble attracting new blood. A report from NIST earlier this year found that the median age for handwriting examiners is 60, compared with 42 to 44 for people in similar scientific and technical occupations. That report, Forensic Handwriting Examination and Human Factors:Improving the Practice Through a Systems Approach, was published by NIST, but was written by 23 outside experts, including Will.

To increase recruitment, the report recommends replacing the unpaid apprenticeships that have been the traditional route of entry into the field with grants and fellowships. The report also recommends cross-training with other forensic disciplines that involve pattern matching, such as fingerprint examination.

The "human factors" in the report's title refers to a field of study that seeks to understand the factors that affect human capability and job performance. In forensic science, these include training, communication, technology and management policies, to name just a few.

Melissa Taylor, the NIST human factors expert who led the group of authors, said that the report provides the forensic handwriting community with a road map for staying relevant. But the threat of irrelevance doesn't come only from the decline in handwriting. Part of the challenge, hun siger, arises from the field of forensic science itself.

"There is a big push toward greater reliability and more rigorous research in forensic science, " sagde Taylor, whose research is aimed at reducing errors and improving job performance in handwriting examination and other forensic disciplines, including fingerprints and DNA. "To stay relevant, the field of handwriting examination will have to change with the times."

Among other changes, the report recommends more research to estimate error rates for the field. This will allow juries and others to consider the potential for error when weighing an examiner's testimony. The report also recommends that experts avoid testifying in absolute terms or saying that an individual has written something to the exclusion of all other writers. I stedet, experts should report their findings in terms of relative probabilities and degrees of certainty.

These recommendations are consistent with findings in a landmark 2009 report from the National Academy of Sciences. Called Strengthening Forensic Science in the United States:A Path Forward, that report said that "there may be a scientific basis for handwriting comparison, " but that there has been only limited research on its reliability.

Knowing When to Not Make a Call

Children used to learn handwriting in school by copying letters and phrases from books that contained models of ideal penmanship. Different copybooks had different styles, and an expert could often tell from a person's handwriting whether they were trained in the Palmer style, the Spencer style, or something else. By identifying a specific copybook style, an examiner could quickly narrow the range of potential writers.

Many children no longer learn cursive writing in school, and whether this helps or hinders handwriting examination is unknown. "It might actually make handwriting more identifiable because it allows people to develop their own individual styles of writing, " said Linton Mohammed, author of the widely used textbook Forensic Examination of Signatures, and a co-author of the NIST-led study.

På den anden side, it might make the task harder by depriving experts of a system for classifying writing styles. This is one reason why research on error rates is needed. The way people learn to write has changed, and error-rate studies can show whether handwriting examiners are successfully adapting to those changes. "We claim to be good at this, " Mohammed said. "But how good are we really?"

Several studies have attempted to answer this question by testing whether experts are more competent at handwriting examination than people with no training. The results reveal a great deal about both handwriting examination and human psychology.

In many of these studies, participants are shown pairs of signatures and asked to determine whether they are both by the same person or if one is a fake. Calculating overall error rates from multiple studies is difficult due to differences in study design. But consistently, across studies, both experts and novices made roughly the same proportion of correct decisions, according to a 2018 metastudy led by Alice Towler at the University of New South Wales, Australia. The novices, imidlertid, made a much higher proportion of errors, while the experts more frequently declined to make a call. If a signature lacked complexity or was otherwise difficult to compare, the experts would more readily find the evidence inconclusive. This ability to defer judgment is critical to reducing errors in forensic science.

The tendency of novices to rush to judgment in cases where experts defer reflects a quirk of human psychology. People with limited knowledge or expertise in a subject often overestimate their own competence. This is called the Dunning-Kruger effect, for the psychologists who first described it. In the case of handwriting, people might be particularly susceptible. Trods alt, pretty much anyone can produce handwriting. How hard can it be to examine?

But error rate studies show that at least some experts recognize their limitations when faced with a difficult task. "I've been doing this for 30-plus years, and I realized early on that there's a lot that we don't know, " Mohammed said. "So we have to be very careful in reaching our conclusions."

The End of Handwriting Examination, or a New Beginning?

Like Emily Will, Mohammed has examined many wills, deeds and trusts. He has also analyzed ransom notes, threatening letters, and one hit list. Being based in the San Francisco Bay Area, where the tech boom has minted many fortunes, he has also examined many stock-option grants and prenuptial agreements.

Although Mohammed started his career with the San Diego County Sheriff's Department, today he is in private practice. In his current home base of northern California, han siger, there are no government laboratories that still examine questioned documents. This reflects a nationwide trend—a report from the Department of Justice found that only 14% of publicly funded crime labs did their own questioned document examinations in 2014, down from 24% in 2002.

Those numbers may mean that the field is consolidating rather than disappearing. If smaller labs can no longer support in-house experts due to a diminishing caseload, they can farm out work to private sector experts like Will and Mohammed. På samme tid, larger federal labs, including the FBI Laboratory and the U.S. Army's Defense Forensic Science Center, continue to maintain questioned document units. This is in part because their focus includes international terrorism, where handwritten documents are still a source of valuable intelligence, and in part because the United States is a big place. Nationwide, crimes involving handwriting still occur frequently enough that federal labs need to keep experts on staff.

When asked if handwriting examiners will soon become irrelevant, one federal expert said that as long as greed and fraud exist, there will be a need for handwriting examiners.

When asked the same question, Mohammed noted that changing technology did not doom the field in the past. "When the ballpoint pen came out, people said, "That's the end of handwriting examination, '" he said. People mostly stopped using fountain pens, but handwriting examination survived the transition.

Melissa Taylor, the NIST expert, agrees that handwriting examination is still a needed skill and will remain relevant—if the field successfully adapts to changing expectations around research and reliability. And if the new report, which counts many leading handwriting experts among its authors, is any indication, the needed changes may already be underway.

"There will still be documents. There will still be signatures, " Taylor said. "And most people don't print stickup notes on their laser printer. They scribble them on the dashboard before running into the bank."

Some things will never change.