From Commonwealth v. Suarez-Irizzary, 2010 Pa. Dist. & Cnty. Dec. LEXIS 380 (Ct. Com. Pl. Aug. 6, 2010):

As technology increases, the law must keep pace. When maps were first created, they represented a cartographer's "best estimate" of where things were located. Since then, measuring wheels, odometers, airplane photography and now global satellite imaging have moved cartography from the realm of human estimating to satellite-verified pinpoint accuracy. When the legal system needs to establish distance with precision, it should not eschew the accuracy that technology now affords in favor of more flawed and primitive means of measurement.

In this case, a dispute has arisen with respect to whether the situs of the Defendant's drug transaction was within 1,000 of a school so as to implicate the so-called "school zone sentencing enhancement". ***

While Pennsylvania has not directly addressed use of satellite imaging systems to determine distance, other states have done so. Interestingly, most of the cases we found that addressed satellite imaging were presented within the context of a "school zone" dispute similar to the one now before us.

In Commonwealth v. Whitlock, 906 NE 2d 995 (Mass.App. 2009), the Commonwealth of Massachusetts sought to prove that a drug sale occurred within 1,000 feet of a school. The Commonwealth presented testimony from a police captain who used a computer program called "Arcview" to determine the distance between the school and the sale. The captain testified that he verified the accuracy of Arcview by comparing the Arcview measurement between two known points with a measurement he personally conducted using a measuring wheel. The Court declared that this type of "calibration" was sufficient to support admissibility of the Arcview measurement. The Court stated: "In each case where a witness testifies that he used a measuring tool to determine a distance, the relevant question is not whether the testimony is hearsay, but whether the foundation was sufficient for introduction of the observed result." ***

In State v. Polanco, 797 A.2d 523 (Conn.App. 2002), the State sought to use a computer-generated map to prove that cocaine was seized within 1,500 feet of a school. The Defendant objected to the map based upon lack of foundation and complained that no one established the accuracy of the computer GPS system used to create the map. The prosecutor called a geographic information systems technician to describe the map's creation and use. This witness testified that he routinely generated distance information using the GPS system. The Court permitted the admission of the computer-generated map and stated: "More specific testimony concerning the underlying technology was unnecessary, and any remaining doubt as to the reliability of that technology went to the weight to be given to the map, not its admissibility." ***

In State v. Franklin, 843 NE 2d 1267 (Ohio App. 3rd, 2005), the prosecution sought to prove that a drug sale occurred within 1,000 feet of a school. To do so, the prosecution proffered a geographic information system specialist who described global imaging software that he used to measure the distance between the drug sale and the school. The Defendant argued that the global imaging software must be supported by expert testimony. The Ohio appellate court disagreed. As part of its reasoning, the Court emphasized that the Defendant had been given notice about the school zone distance and the prosecutor's methodology of calculating that distance well in advance of trial. The Court stated that the Defendant therefore had the opportunity to conduct his own measurements in order to refute the State's computer-generated calculations.

In State v. Young, 902 So. 2d 461 (La.App. 2005), a police officer testified at trial that a drug sale occurred "approximately" 150 feet from a school. The Court testified that the police officer's mere estimation of distance, without more, was insufficient to establish that the drug sale occurred within Louisiana's 1,000 foot school zone. On appeal, the prosecution attached maps and measurements generated by the computer program "Map Quest" to verify that the drug sale did in fact occur within the school zone. The prosecution asked the appellate court to take judicial notice of the measurements derived from "Map Quest". The Louisiana appellate court refused to do so and determined that some supporting testimony would be needed in order to accept the Map Quest measurements.

As we sift through all of the above, we reach the following conclusions with respect to the admissibility of computer-generated satellite imaging distance calculations:

(1) Courts should not take judicial notice of computer-generated satellite maps.

(2) Authenticating evidence will be required before computer-generated satellite-based distance calculations are admitted in evidence.

(3) Neither expert testimony nor testimony from those who created the satellite imaging system are necessary in order to authenticate maps or distances derived from the use of the satellite mapping system.

(4) Computer-generated determinations of distance can be authenticated when an individual testifies that he/she verified the accuracy of the computer program by comparing a computer-generated distance between two known points with an independently determined calculation of the distance between the same two points.

(5) In order to prevent undue prejudice from the use of computer-generated satellite-based imaging systems, the Commonwealth must produce the identity of the imaging system and the results of its usage to the Defendant sufficiently in advance of its proffered use that the Defendant can make independent calculations and/or dispute the accuracy of the system.

Based upon the legal conclusions we have derived from our research as outlined above, we determine that the Commonwealth's use of the Google Earth technology was properly authenticated when Detective Walton testified about his familiarity with the Google Earth system and his independent verification of Google Earth's accuracy using two known points that Detective Walton himself measured. In addition, it was plainly apparent to us that the Defendant was well aware in advance of sentencing that the Commonwealth intended to produce a distance measurement calculated using Google Earth. The Defendant therefore had ample opportunity to make his own distance calculations and/or challenge the accuracy of Google Earth.