Preserving Marine GPS Data Expert Article

In this article, the digital forensics experts at Robson Forensic discuss the use of GPS data within marine disputes. The discussion includes the proper collection, preservation, and analysis of data.

Marine GPS Expert

Preserving Marine GPS Data - Expert Article

When a vessel is involved in an incident, the GPS unit should become evidence. It is important that the digital evidence, especially the GPS track data, is completely extracted and preserved.

Our experts interpret this data within the context of specific events to reliably answer questions involving speed, location, and many other relevant issues. Data can help support or refute eye-witness testimony.

Figure 1: Garmin GPSMAP 2206 with a Saved Track


Above is a picture of a Garmin GPSMAP 2206 with a saved track displayed in blue and named “VESSEL 1.” Too often we receive discovery very similar to the picture above and are told that is what another party, investigator, or examiner “preserved” as the digital evidence from the GPS unit.

This is not a best practice as there is much data that is not preserved, thus critically limiting the ability to analyze and present the data. Depending on the quality of the image and the detail and accuracy of the basemap, even the photos of a track display can be rendered useless in determining precise locations or speeds.

A proper extraction and preservation of GPS digital evidence preserves all the GPS track data in addition to the specific setting on a unit that describes that data.

Often, the extracted evidence is able to be displayed on a basemap with other relevant information. The graphic below shows the same track seen in the Garmin GPSMAP2206 in blue in addition to a different track from a second vessel in red.

Figure 2: Extracted Data Display on Basemap

Based upon the information above, we can see that at the time of collision Vessel 1 (in blue) was traveling approximately 12 mph and Vessel 2 (in red) was traveling approximately 65 mph after making several loops to starboard.

The animated video below depicts some of the advantages of extracted data and how that information can be used to create effective demonstratives.

GPS & Mobile Device Data Investigations

The experts at Robson Forensic have specialized training, education, and experience to extract data from a broad range of systems and devices and interpret that information within the context of a specific incident.

Contact your local robson forensic office or submit an inquiry to discuss your case and determine how robson forensic can assist with your investigation.

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