A Clear Case

Two years before GIS maps were used as evidence in a murder trial in Kent County, Michigan, prosecutors there got their first glimpse of how powerful geospatial technology could be in court.

The case for GIS started with a strange incident. Kent County GIS analyst Brodey Hill was jogging during his lunch hour when he encountered a bizarre scene: nearing a busy intersection, Hill was shocked to see a man streaking in front of commuters.

“I just kept running, hoping someone had already reported him,” says Hill. Later, on his way back to his office, he spotted the man walking toward him. “I confronted him about his behavior, which made him belligerent.” Concerned that other pedestrians would soon be threatened, Hill decided to detain the streaker until police arrived. The man resisted, and a wrestling match ensued between Hill and the suspect. Police arrived and broke up the fracas. Hill cleaned himself up and returned to work, thinking he’d seen the last of the man.

But the suspect decided to fight a charge of indecent exposure, and Hill was subpoenaed as a witness at the trial.

“The prosecutor had been using Google Maps to depict the scene of the crime and establish his case,” Hill said. The images were spartan, consisting mainly of web screen grabs with no symbols to orient the jury. “When I saw those exhibits, I knew that more professional maps could demonstrate the prosecution’s case better.”

Using Esri ArcGIS, Hill created oblique aerial views of the crime scene populated with features. The more detailed exhibits showed that the defendant exposed himself in an area of downtown viewable from numerous angles, thus corroborating the public indecency charge.

That trial introduced the county prosecutor’s office to GIS. As a result, the power of professional mapping became a hot topic of conversation at the office and eventually led to Kent County law enforcement officers, the county prosecutor’s office, and Hill to collaborate on a murder case and use GIS to map cell phone location data in the trial of Karl Cotton, Jr. Cotton was eventually convicted of killing 30-year-old Jamie Powell.

About the author

Matt DeMeritt is a copy writer and brand journalist for Esri. For more than a decade, he has written articles about everything from mapping invasive pests to mapping the moons of Saturn. Prior to joining Esri, he was an English tutor at California State University, San Bernardino.