Regarding Gait:
It is impossible to fully, confidently and accurately assess someone's gait to identify meaningful deviations, movement impairments or physical causes/disorders/dysfunctions with a casual stroll in full street clothing, let alone when wearing tactical gear, a helmet, boots, and while carrying things, and certainly not from a blurry, two dimensional low frame speed acutely angled distant camera lacking depth. No one, not even a regarded forensic podiatrist (who has hopefully extended his breadth of knowledge to include everything above the ankle as well which would be incredibly rare for a podiatrist) nor a very highly skilled experienced physical therapist can. I cannot imagine testifying under oath to anything beyond the gross professional generalizations, observations and opinions I will list here. Which frankly would only help a defense team.
Firstly, there is no one "normal" gait. We all have to move and function the best we can with what we have, at this point in our lives and our bodies will ALWAYS seek the path of least resistance to complete a functional movement. My job was to optimize and maximize function, not find an imaginary normal. In this case, I don't see a clear bodily root cause for the toe out and right "limp" because I can't assess under these circumstances and could only make low confidence educated and experiential guesses. I can very easily see the toe out and intermittent "limp" as nothing more than an effect of tall tightly laced boots limiting ankle dorsiflexion (upward bending of foot towards the shin). There isn't a wide range of plantar flexion or dorsiflexion observed and I believe the boots are probably the cause.
People primarily limp because of pain, loss of mobility, weakness (usually in the buttocks), any number of habits (perhaps they have always sat with the same leg crossed over the other causing stretch weakness and pelvic instability for example), body build/habitus or perhaps they just learned to limp after an injury and never addressed their residual dysfunctions or retrained themselves. Or any combination of that. When ankle dorsiflexion is limited or restricted, out go the toes to clear the foot when walking - almost without fail, it's easier than buckling your knee (path of least resistance). You'll see the same thing with someone wearing a walking boot, toes go out even in a well-fitted walking boot. Perhaps SP's right boot was tighter than the left, or the tongue of the boot shifted and was irritating the foot, or they were developing a blister because they aren't used to wearing these boots and they've probably had them on for hours and wasn't smart enough to put on two pairs of socks. I am literally a professional observer of human movement and function who can't say with any confidence what impairment could be contributing to the foot position or limp with the limited observations I can make, nor identify any underlying neurological deviation or musculoskeletal cause.
Secondly (and bear with me), strolling isn't the same mechanics as walking, jogging or running. Walking at 2.0 mph is also not the same mechanically as walking at 4.0 mph and so on. Jogging in place is not the same as jogging forward. And with rare exception none of these would be expected to be the same if you compare barefoot to athletic shoes on. And certainly not with boots. Virtually no one jogging in place on a hard surface barefoot will land flat footed. They will land first on their forefoot and maybe drop their heels to the ground. And virtually no one will jog across a hard surface barefoot the same as if they were in their running shoes or on a padded surface. If you are exclusively a forefoot jogger then maybe, but it hurts if you are not that to smack your heels on the ground, so normally heel-strikers will immediately jog on their mid or forefoot and don't even realize they are if you take the shoes away. I could go on, but the points here are 1 - a complete and meaningful gait assessment can be extremely complex depending on the individual and therapist and we don't look only at casual strolling, and 2 - People will quickly and unconsciously alter their gait significantly for any number of reasons, including surface, shoe, something in their shoe, and other environmental reasons. Not just their bodily limitations. I could also really go out on a limb and say because SPs sight line and hearing were probably limited by the helmet, and we use all of our senses to orient ourselves, that maybe they just turned their feet out a bit more to seek stability by widening their base of support.
Thirdly - there's also no one normal foot posture. Normal is just considered to be flexible, adaptive and having the ability to become stable and create an arch at big toe push-off AKA the windlass effect for the curious. Please don't chime in and say "but my pronated flat feet ..." because that alone doesn't necessarily mean you will have problems or limitations and I won't get into that debate. I have seen absolutely gnarly foot and toe alignments that don't bother people at all. Do we fix something that isn't problematic or limiting? No. Look at lean Kenyan and Ethiopian marathoners who are inclined to have very flat feet yet are at the top of their sport and often run barefoot. Look at Pacific Islanders feet. As a general population, they tend to be the opposite - larger and heavier individuals, who don't often wear supportive shoes, and typically wear "slippers". I can honestly say in my nearly 30 years of being a physical therapist, I have treated one Pacific Islander with plantar fasciitis and that was only because they stepped hard on a rock and bruised the tissue and bone. Not because of their obesity, inactivity or flat feet. Feet are very complicated enigmas to say the least.
I'd also like to point out that how one walks after 30 minutes isn't usually the same as the first few minutes of getting up and going after sitting, or after two hours on your feet. Running assessments are miles long sometimes. I'd have patients run 9-10 miles right before they came in to their appointment and hopped on the treadmill to continue if their pain kicked in at mile 11 to see what was changing at that moment. Point 3 - ALL movement patterns predictably change over repetitions and time. Sometimes they get better, sometimes they get worse. They can vacillate. Sometimes it takes seconds, sometimes hours. My golf swing on hole 16 is definitely not the same as it was on hole three. How does your toe touching look after 10 reps? 20 reps? We can't take 30 seconds of video and just assume this is how the person typically walks day to day - unless perhaps they are typically wearing and used to wearing this outfit. Which I highly doubt is the case. And now it's eight years later, and likely something has changed physically with SP which one could easily argue would negate any comparison. And I have to think the weight of carrying a murder around with you might lead to some physical changes.
To reiterate, there's no specific cause of the toe out or limp anyone, with any credentials, can accurately or with full confidence identify or diagnose and that can't be dismissed for some reason or another with what we see. Even thirty minutes of this quality video likely isn't enough and I don't see how any of whatever speculation provided by the podiatrist would be helpful if a suspect gets to court unless they have some HD cameras and angles we haven't seen and that's still a stretch because they are geared up and completely covered. There are so many things it could be and I could take some mechanical guesses, but because both feet at different times and multiple times return to a very average 10ish degrees of toe out at different points of strolling the SP clearly isn't stuck in this toe out position. They just aren't. So it's entirely plausible and perhaps likely this isn't how they normally walk.
FWIW IMPO the way SP stands, transitions, strolls and also runs their fingers along the wall is more telling as being female than male. Nothing about how SP swings a hammer would indicate SP is a female, just someone who I see as calm, careful, intent and not vested in destroying property by beating it hard or risking accidentally sending one of their intended murder weapons through the peep window in the locked door they are trying to break in to, or to accidentally hurt themselves in the process. SP's elbow carrying angle also does seem to indicate female (females have wider pelvises, so our elbows angle out further) but again the camera angle and clothing bulk doesn't help and I wouldn't risk my reputation on it. We can't see enough of SP pelvis or trunk motion details to weigh that in, another beauty of black clothing and waist packs/pockets - it hides things.
I did play with the video and tilted the image so the legs of the glass table in the hallway next to the garbage can were vertical, and when SP walks right past it I would assume this also makes SP vertical or at least not nearly as distorted as the downward camera angle did. It did change some things, including the shoe shadow which when not adjusted consistently makes the boots look bigger. Changing the image angle also changes the foot size to the extent the boots can look quite normal in size. So I'm not convinced they are oversized.
SP is gross motor right handed (R shoulder is more forward and lower). Doesn't mean they write or do fine motor skills right handed. Or does anything else for that matter right handed. You'd likely be surprised how many people do everything left handed but hammer right handed or vice versa. Or do everything right handed but shoot basketballs left handed. Hammering is literally the question I ask if someone says they are ambidextrous, "which hand holds the nail and which swings the hammer". Only a lifetime contractor will tell you they're just as good R or L handed hammering.
SP has a forward head, and likely a flattened lumbar lordosis, posterior pelvic tilt. So I'd guess they either sat for work at a desk job, or is genetically predisposed to a dowager kyohotic type posture. Or just doesn't care about their slouchy stature.
Hoping this might put the gait head scratching on the back burner for some of you, and that the investigators focus attention elsewhere. Now everyone go move for a 20 minutes!
All IMO with a professional expert spin.
