Getting evidence with a low cost, low tech drone flight over a forensic site

Aerial video of a failure or accident site taken from a drone is one of the lowest cost, lowest technology tasks ever in forensic investigation.  And one of the best ways of getting and presenting evidence.  Like $285 for 34:41 minutes of video on one of my recent investigations.

And if you like, yours could be taken with a GoPro camera, like those on an Alpine skier’s helmet, borne aloft on a Walmart drone.  I’ve seen GoPro-Walmart quality video of a P.E.I. beach scene taken by a hobbyist and it was good.

My aerial video is taken by a photographer who does contract work for CBC (recently on assignment getting Canadian 150 year birthday video) with multi-thousand dollar equipment, for the Walmart charge-out fee, and his footage of my forensic sites is excellent.

It’s also a feel-good task as well as low cost, simple technology.  You’re seeing the site in a different and revealing way.  You know you’re getting lots of valuable data captured on 1,000s of frames for study of any one or more later.  You can even measure features on these frames by placing large “rulers” on the ground in different positions before your flight – simple “ground control” in land surveying jargon.

I was prompted to mention this when a reader remarked that he didn’t think his forensic investigation needed high tech aerial video of an accident site.  (It doesn’t, based on his description of the site, but this kind of technology came out in a remark of mine about different engineering methods)

He could be excused for thinking like that, particularly in light of the recent, front page Globe and Mail coverage of the new, much-needed DOT regulations governing recreational drone flights.  The regulations are strict and penalties severe if you don’t abide.

They are needed when you learn how quickly you can climb hundreds of feet – and into a plane’s flight path.  Or zip around a multi-story building – and into a closed window.  In fact, think stings-like-a-bumblebee because that’s the speed and faint background sound you get as you videotape a failure or accident site.  My professional photographer abides of course.  We have been for a couple of years since he started taking low cost aerial video of my forensic sites.

The take-away from this is the valuable data you get with low cost, low tech aerial video – and feeling good and having fun while you’re getting it.  The photographer flies the drone while you direct the video coverage from the “co-pilot’s seat”, a flight monitor on a tripod nearby.  This technology is certainly not applicable to all investigations as my reader noted but valuable when it is – and an impressive way of presenting evidence to the judicial system.

(Hello: Read some of the blogs below, for sure, #5, to get a feel for the valuable expert data possible with a low cost aerial video of your site)


  1. “Crewing” on a forensic drone flight.  Posted October 4, 2016
  2. U.S. civil litigation lawyer on using air photos in environmental litigation.  Posted November 18, 2015
  3. Fixed wing drones – another tool in forensic engineering investigation.  Posted November 4, 2015
  4. New forensic aerial photographic method proving extremely valuable.  Posted January 30, 2015
  5. A picture’s worth a 1000 words, possibly many 1000s in forensic engineering with a new aerial photographic technique.  Posted January 15, 2014 (See frames from a demonstration drone flight in this posting)

Managing the cost of civil litigation when experts are involved

Forensic investigation of the cause of a failure or accident in the built environment doesn’t always require an exhaustive investigation of conditions at a site.  And civil litigation doesn’t always need to bear the attendant higher costs.  Sometimes but not always.

There is a point at which the cost of the data obtained and the time required to get it outweigh the benefit of the data, the increased certainty of the opinion and the quicker resolution of a dispute.

The answer is early involvement of an expert in consultation with counsel.  And the two working together to identify the key technical issue(s) in a case.  It works best when counsel seeks to understand these issues early and rises to his responsibility to explain them to the judicial system. (Ref 1)

I’ve had some cases that settled in a heart beat after the investigation of a single, simple technical issue.  One case settled in four months after 11 years of litigation.  There have been other investigations that have been longer and more expensive.

There is a judgement call on the necessary level of investigation.  Should this technical issue be checked out or that evidence followed – as in the seemingly cast-in-stone edict, “Follow the evidence”?  The call is best made by an experienced expert and a suitably informed counsel.  The cost of civil litigation is often less when this is done wisely and well.

It also sometimes helps if counsel visits the site and “gets his hands dirty and mud on his boots” – sees what’s out there and some of the investigative work being done and why. (Refs 2, 3)  I know of one slip and fall accident that was cinched because counsel came to the site, sat down and watched me work.  In this case, carrying out two quite unusual tasks that carried the day.

Cutting costs can’t be done in a cavalier manner.  I’ve seen this happen too and the injured party likely get the short end of the stick in one case.  Litigation is expensive, and reliable, expert data costs money, but it can be managed.  It doesn’t always need to be exhaustive.


These thoughts came to mind a few days ago when I was reviewing the principles governing Phase II ESAs (environmental site assessments) as given in an ASTM standard. (Ref. 4) These environmental assessments have strict requirements.  I know, I’ve done them – but there are some “that do not … require an exhaustive assessment”.   When I read that in the standard, I was reminded: That’s the way it is in forensic engineering investigation.


  1. Principles governing communicating with testifying experts.  The Advocates’ Society, Ontario, June 2014.  Posted June 11, 2015
  2. An expert’s “dirty hands and muddy boots”.  Posted December 20, 2013
  3. Counsel: Your case benefits when you visit the scene of a personal injury or engineering failure.  Posted April 30 , 2016
  4. ASTM E1903-11 Standard Practice for Environmental Site Assessments: Phase II Environmental Site Assessment Process, ASTM International, West Conshahecken, PA, 2011