As a followup to our introductory post, Gretchen and I wanted to explore the many different types of evidence, and talk about their differences, even before getting into the legal definitions and ramifications. Whether you're taking a photo, reading data from a sensor, or cataloging health symptoms, we'd also like to ask what types of information you're interested in using as evidence, and we'll do our best to follow up on each type over the course of the series.
Evidence could mean something used in a legal case, like Scott Eustis's work in photographing coal contamination by United Bulk in the Mississippi. It could mean creating a map to establish land tenure claims, as Maria Lamadrid has worked on in Uganda. Or it could mean analyzing microscopic pictures of dust to quantify particulate pollution.
We want to cast a wide net here, so for starters, we're looking at a number of broad categories of potential evidence:
- physical samples of air, water, or soil
- digital sensor readings of many types
- photographic, audio or video records
- timelapse, infrared photos, thermal or microscopic photos
- photo metadata, such as timestamps or GPS data
- colored strips of paper or indicator tubes, like litmus tests
- also, photographs of such colorimetric indicators
- spreadsheet data resulting from an analysis of, for example, images or sensor data (we have a specific case in mind for this)
- human sensory data collection -- like odor logs or direct visual monitoring
- health symptoms in animals
- human health symptoms
This is a huge topic, and the more we dig in, the more diverse understandings of the term we encounter. In discussions with some of our interviewees for this series, we've encountered distinctions between screening and analytical samples, and samples used in enforcement processes or to gauge remedial progress. We'll look into these to learn more, and get back to you. Can you suggest other types?
Note that the item above, about spreadsheet data, is especially interesting to us -- that is, what about lab analyses themselves? Does a report about a sample or a measurement constitute evidence? Some of the above examples (like this one) are drawn directly from projects we're engaged in, and we'd love to hear from others about specific real-world cases involving different types of evidence.
For one, we're interested in how microscopic photographs of air pollutants like silica (above image by @mathew), and the associated datasheets from their analysis, can be properly collected, stored, and presented as evidence. How does maintaining a chain of custody work with digital data? Do equations in a spreadsheet need to be preserved and documented along with the data themselves? How is that best done -- do we need to, for example, keep a log of timestamps and authors for each edit?
One thing we came across in our exploration has to do with the use of spreadsheets in court, and was hard to believe! Cogent Legal runs a pretty interesting blog on preparing evidence (and derivative graphics) for court, and discussed the logistical and procedural challenges to using or even adding to a spreadsheet used in evidence:
One of Cogent Legal's clients recently went to trial with a spreadsheet similar to the one used for this post. The spreadsheet printed out to be 28 pages long, and the original column had no total on it. For a printed exhibit at trial, counsel added a total to the spreadsheet, but opposing counsel objected to its admission, arguing that the spreadsheet had been altered and lacked foundation. Thus, the attorney offering the spreadsheet as evidence displayed the electronic spreadsheet for the jury on a courtroom screen, and then led the witness through the process of summing the column's total in Excel. Once this total was established, the opposing counsel stipulated to admission of the original document (and also stipulated to the admission of many similar documents). -- http://cogentlegal.com/blog/2014/06/excel-for-litigators/
We'll be looking to compile some best practices to -- hopefully -- avoid that kind of painful walkthrough.
Another usage we're exploring is #timelapse photography (above timelapse by @tonyc) -- useful in monitoring all kinds of activity over long periods of time. There are EPA recognized techniques (like Method 82) which employ timelapse photography of smoke plumes. Folks at LEAFFEST 2016 will be trying out some timelapse methods, and we'll want to know how this sort of evidence ought to be handled as well.
In any case, we'll surely be updating this post as we discover more, and we appreciate any additions you can offer! Thanks, and stay tuned.