June, 2018

Larcenies Increase, Recidivism Declines in California after Prop 47

A report released June 12, 2018, by the Public Policy Institute of California, “The Impact of Proposition 47 on Crime and Recidivism,” examined the effects of Proposition 47 (“Prop 47”) on crime rates and recidivism. Prop 47, which was passed by about 60% of California voters in 2014, modified, or reformed, the California criminal justice system in several significant ways. Certain offenses were reclassified from felonies to misdemeanors. Those “Prop 47 offenses” are check forgery (under $950.00), receiving stolen property, personal use drug possession, shoplifting (under $950.00), most theft offenses (under $950.00), and writing bad checks (under $950.00).

Prop 47 followed changes in California’s criminal justice system in recent years. Between 1980 and 2006, California’s prison population had increased seven-fold. Federal courts, between 2009 and 2011, required that the inmate population be decreased by 34,000 inmates. In 2011, legislation transferred the responsibility for most non-violent, non-sexual offenders to county jails and probation services.

Prop 47, which applied retroactively, earmarked 65% of net state savings from reduced incarceration costs to be transferred to mental health and substance-abuse grants and programs.  By December 2016, the state prison population had decreased by more than 15,000 inmates. Within one year of Prop 47’s passage, arrests had declined by 5%, and “cite and release” tickets increased by 14%.

Crime rates, which the report indicates have been historically low, did increase in 2015 and 2016; the report concluded, however, that for violent crimes and most property crimes the increases were unrelated to Prop 47. For example, the FBI in 2014 expanded the definition of rape to include additional behaviors; that new definition had the effect of increasing reported rapes in 2014 by 38%. Theft offenses, particularly thefts from motor vehicles, did increase – about 9% – due to Prop 47. Reported shoplifting offenses saw an increase, but the number has since declined; thefts from motor vehicles have not declined.

Statistics from 12 California counties – which represents about 60% of the state’s population – found that bookings into jails decreased by about 8% in the year after Prop 47 took effect. However, the declines were seen in the white and Latino populations, and not in the African American population. For example, before Prop 47 took effect, 21.6% of the jail bookings were African Americans. One year later, 22.3% of the bookings were African Americans.

Before Prop 47 took effect, 2/3 of the people charged with Prop 47 offenses were charged with felonies; one year after it took effect, less than 1/3 of people charged with those offenses were charged with felonies. Overall jail bookings declined by about 10%, as more of the offenders were diverted into alternative programs for Prop 47 offenses.

Concerning recidivism, the report found lower arrest and conviction rates for Prop 47 offenders but noted that it could not determine whether offender behaviors were necessarily modified or the extent that changes in practices in the policing and prosecuting agencies had upon the data. For all offenses, there was a 1.8% decline in those rearrested for offenses after Prop 47 took effect. Drug offense rearrests declined after Prop 47 by 11.3%; there was no marked difference in rearrests for property crimes. Reconviction rates were similar.  For all offenses, there was a decline of 3.1%, and for Prop 47 offenses, there was a decline of 11.3%.

The report concluded that, while Prop 47 is still being debated, the prison and jail population problems have been prioritized, there has been a decrease in recidivism, rearrest, and reconviction for property and drug offenses, but a “complete assessment of the impacts of Prop 47 will need to account for how increased interventions may affect crime, criminal justice contact, and recidivism, as well as responses by law enforcement to the reform.”

Sources:  Don Thompson, “Thefts rise after California reduces criminal penalties,” sacbee.com, June 13, 2018:
Mia Bird, Magnus Lofstrom, Brandon Martin, Steven Raphael, and Viet Nguyen, with Justin Goss, “The Impact of Proposition 47 on Crime and Recidivism,” Public Policy Institute of California, June 2018:

Manipulation of Video Forensic Evidence

A recent article described how digital visual media forensics (“DVMF”) is helpful in ascertaining the authenticity and reliability of digital information. DVMF is a research field that develops and provides investigative procedures and techniques to authenticate images and videos, which “are incredibly easy to manipulate.” The researchers use “evidence theory,” also known as The Dempster-Shafer Theory and, also, the Theory of Belief Functions. Evidence theory is a mathematical formalization and theory of evidence that allows for the combining of evidence, or pieces of information, from multiple sources (evidence theory-based decision fusion). The collected evidence may be contradictory or incomplete; when combined under the system, however, the researchers can arrive at a collective degree of belief in the trustworthiness of the evidence. Key to the DVMF process is the Locard’s exchange principle (“every contact leaves a trace”).

The DVMF process looks for the forensic artifacts left when a digital image or video is manipulated. The article author noted, “Every operation that is applied to a digital image or video, and which alters its composition in some way, leaves behind subtle evidence of its occurrence.”

Researchers employing evidence theory-based decision fusion first seek to recognize and denote a set of all possible conclusions that can be reached. Next, forensic researchers will undertake probability assignment, where probabilities are assigned to all subsets involved in a proposition. A set of all subsets is called a “frame of discernment”; each element in a frame of discernment is assigned a probability.

Anti-forensics has developed as a forgery technique to hide unauthorized modifications of digital images; a forger will try to erase the traces left by the contact. Counter anti-forensics has developed to combat the anti-forensic techniques because the forger’s attempts to erase the traces – consistent with Locard’s exchange principle – “inexorably leave behind certain identifying traces of their own.” The article author noted that where a digital image is suspected of having been manipulated, forensic analysts should integrate counter anti-forensic techniques into the forgery detection systems. If both regular and counter anti-forensic tools yield are utilized, and no inconsistencies are detected in the image, then there can be greater confidence in the authenticity of the digital content.

The author concluded that an evidence-theory-based multi-clue framework, which allows the combining of contradictory or incomplete pieces of information from multiple sources, was superior to a simple forgery detection system.

Sources:  Raahat Devender Singh, “Digital Visual Media Forensics: Has That Evidence Been Manipulated?” forensicmag.com, June 6, 2018:
Related:  Raahat Devender Singh and Naveen Aggarwal, Ph.D., “The Science of Discerning the Real from the Fake,” forensicmag.com, December 8, 2016:

by Neil Leithauser
Associate Editor