Koehler was also able to demonstrate that the treads of the ladder originated from parts of the staircase and flooring in the attic in the property in which Hauptmann lived. Crucially, a part of the ladder, exhibited in the trial as ‘rail 16’, matched a sawn-off floorboard in the attic of Hauptmann’s home. The pattern of the annual growth rings of the wood and their curvature on rail 16 and the floorboard were an exact match. On top of this, Koehler also demonstrated that four empty square-cut nail holes found on the ladder’s wood were a match for the distribution of the missing wood and nail holes found in the attic.
Shortly after the trial, Koehler was interviewed on radio and stated ‘In all the years of my work, I have become convinced of the absolute reliability of the testimony of trees. They carry in themselves the record of their history. They show with absolute fidelity the progress of the years, storms, droughts, floods, injuries, and any human touch. A tree never lies. You cannot fake or make a tree.’ While his proclamation may seem rather grandiose, basically he was right. I don’t think anyone has yet managed to fake tree rings! However, we are all capable of misinterpreting what we see before us. One of the key requirements to be a good scientist is to ensure that your conclusions can be supported by your observations.
Another requirement is: don’t rush. Rushing work to keep clients happy is never wise. To the best of my knowledge, I have only made one mistake in my work for the police. I misidentified a leaf. I foolishly attempted to identify the leaf from photographs supplied by the police. Based upon my observation, I though the leaf was of value evidentially. Photography can be a very valuable tool, but it can also be very misleading, and in this case, I allowed myself to be misled. The angle from which the photo was taken obscured some of the features necessary for correct identification. Hours later, I received an extra batch of images from the police that showed I had misidentified the leaf. As a consequence, it was not evidentially important. After a few moments of cold blood running through my veins, I picked up the phone. Although the detective was polite, I could sense the gritted teeth. Police forces quite often ask my opinion based upon photographs taken by their own team. Unfortunately, I’ve yet to meet a botanically inclined police officer, and they invariably take awful pictures of plants and vegetation in general. The images are either landscape scale and not focused on the vegetation, or they are somewhat abstract images of part of a leaf or a flower. It’s not their fault; without proper training they won’t be able to photograph the salient features of a plant or vegetation to aid identification or to get a botanical feel of a crime scene.
Although the Lindbergh case is sometimes described as the first case of botanical evidence used in serious crime, there are earlier instances. Indeed, near the start of his testimony at the Lindbergh trial, Koehler explained that he had prior experience of criminal investigations. In 1923 Koehler gave evidence at the murder trial of John Magnuson in Wisconsin. Magnuson, a farmer, was involved in a disagreement with the local authorities over plans to dig drainage ditches across his land. On top of this, they planned to tax him to pay for the work. As the dispute escalated, a dredging machine loaded with 200 gallons of gasoline and diesel blew up. Although foul play couldn’t be proven, many suspected it was not an accident and blamed Magnuson. Finally, two days after Christmas, tragedy struck when a pipe bomb was sent, disguised in a parcel, to the home of James Chapman, a county commissioner and enemy of Magnuson. The bomb severely wounded Chapman and killed his wife, Clementine. Koehler testified at the trial of Magnuson, by then known as the Yule Bomber, and by using microscopic comparison was able to show that the white elm (Ulmus americana) wood used to house the device was the same as some of the wood shavings taken from Magnuson’s work bench.
So, Koehler had previous experience of examining wood as part of a criminal investigation. Sensing that his testimony could prove damning, one of Hauptmann’s defence team, Frederick Pope, attempted to prevent Koehler from proceeding. Pope objected by saying that ‘this witness is not qualified to express an opinion regarding wood’, which he further qualified by adding, ‘We say that there is no such animal known among men as an expert on wood; that it is not a science that has been recognized by the courts; that it is not in a class with handwriting experts or with ballistic experts. But this is no science, this is merely a man who has had a lot of experience in examining trees, who knows the barks on trees and a few things like that.’ Pope then proceeded to liken Koehler’s knowledge to that of members of the jury − it was ordinary and of no particular merit. His attempt failed and, after some probing of Koehler’s qualifications and experience, the judge, Thomas W. Trenchard, declared, ‘I would say to counsel now I deem this witness to be qualified as an expert.’. Trenchard’s statement is a pivotal moment, when the use of botany in criminal investigations was acknowledged to be on a comparable footing to other science-based techniques such as fingerprint analysis.
Kohler’s experience of a barrister attempting to reduce his experience to that of someone who ‘knows the barks on trees and a few things like that’ is reflective of a deeply ingrained ambivalence to plants in our societies. It is also true that this ambivalence towards botany and environmental forensics often still plays out when I attend a crime scene.
6
The Layby
The longest and most complex case I have worked on involved the awful murder of a woman who had been savagely killed by her estranged husband. He beat her to death while their children waited for her in another part of the house. With the knowledge of family members, he then drove to a secluded spot and dumped her body.
Shortly afterwards, he was arrested and charged with her murder. Unfortunately, despite repeated interviews, the suspect was either unwilling or unable to lead the police to the woman’s remains. The family members who assisted the suspect confessed to having helped him dispose of the body in a layby. They and the suspect claimed to not remember where. Initially, the police had limited information to go on regarding her whereabouts, witness statements were vague and potentially unreliable. After much painstaking work involving mobile phone signal data, automatic numberplate recognition (ANPR) and appeals to the public, the police believed that they knew on which stretch of road her remains were. Unfortunately, the area was still very large, approximately 10 miles of major road, much of it dual carriageway. After several months of searching laybys along the stretch of road, the police decided to seek the professional skills of the forensic anthropologist Sophie.
Sophie calls me to assist with the search. There are numerous laybys along the route. So far, the police have largely concentrated their efforts on two of them. They have a long way to go. Before arriving at the scene, I receive various maps from the police detailing the search areas. These arrive either on encrypted CDs or via secure email. I also have quite a long discussion on the phone with Sophie. The first site we are surveying is large and complex, with a range of ditches, ancient hedgerows, streams, woodland and pasture. This land is adjacent to a large and heavily used layby on the main road. It is going to be noisy. It is also likely that we’re going to attract the attention of the press.
After a longish journey from London, I arrive early in a small town in northern England. It’s fairly affluent but there still isn’t a decent coffee shop around. I mutter to myself and grumble away because I’ve been up since about 5 and I hate mornings. It’s also bloody freezing; after 30 years in London I’ve become soft. I used to be tough. The house I spent my early teens in during the early 1980s was so cold that one winter a glass of milk by the side of my mother’s bed froze solid overnight. I brace myself for meeting Sophie; she’ll be fully conscious and requiring my undivided attention, quite rightly so. Her car pulls up and I stumble forward. As we drive out of the town and get onto the bypass, Sophie runs through the case again while I strive to look intelligent. She knows me well enough by now to realise it’s a sham. We also catch up on gossip: how are things in her office, how’s life in the museum, what have her children got up
to, that sort of thing. I enjoy Sophie’s company − she’s got a sense of humour and a forthrightness that is very much to my liking. Both of us would make terrible poker players because our faces generally depict quite clearly what we think of others and their decisions; especially if we think they’re being dumb or bullish!
As we near the layby, I can see two police vans, a marked police car and an unmarked car. The latter will probably be the detectives’. The landscape is very flat, a typical flood plain. I can already sense what the soil will be like. I have a rough map of the geology of England in my head and based on that I’m quite good at assessing soil types from a car window. I’m also playing a small mind game with myself – predicting what plant species I’ll encounter once I step out of the car. Parts of the landscape are clearly rather old, as the hedgerows look ancient even from a distance. On the other hand, the wood is very recent in origin, probably less than 30 years old. No doubt it was planted to shelter the nearby housing estates when the bypass was built. It looks like a woodland and has largish trees, but its ground flora will be very limited. To me this is not woodland, it’s plantation. I force myself to fully engage my still half-numb brain. As I step out of the car, my reacquaintance with the cold helps. I also remind myself that each police force and investigating team is different. I have to learn the behaviours and foibles of each new team as I come into contact with them. Generally, this involves me keeping my mouth shut for a while. It won’t last.
I soon realise that I have worked with some of the team before. Overall, I’m happy because I’ve worked with this force several times and rather like them. But I also know that I’m going to have to live off crisps, chocolate, instant coffee and packet sandwiches for the next few days, all of which will be consumed in the snug confines of the police van or while standing on the roadside. After the introductions, I promptly forget everyone’s names, even the ones I’ve worked with before (I’ll have to badger Sophie about that later, as she’ll know). We then discuss the scene as a whole and review some of the information (for example, mobile phone data) that led the police to search this location. After the initial briefing I take myself off for a look at the plants. This is to familiarise myself with the ecology of the area and to further reassemble my mind. It’s now about 9.30 and about time I woke up! Feeling a bit smug, I’m quite pleased that my car-bound assessment of the vegetation is largely correct. The grassland is actually more interesting than I’d imagined. It’s quite species-rich but is sadly neglected because there has been too little grazing or cutting for hay. Tree saplings are beginning to establish, and in another decade or so the grassland will largely be gone. This really peeves me because species-rich lowland grasslands are some of our most endangered habitats, far more so than woodland, and to date we’ve lost over 97 per cent of them.
We decide to focus our efforts on the most likely areas for a hurried burial late at night − those most accessible from the layby and the side of the road. Even a small dead person rapidly feels very heavy when being moved, and it is rare for a person’s body to be carried or dragged more than 50 metres unless the perpetrator is very athletic. We start with the ditch and adjacent vegetation running along the edge of the layby. It is about 200 metres long and 8 metres wide. It is also quite deep, in some areas well over 2 metres, and with steep sides. Not surprisingly, because it’s been raining almost non-stop for about ten days, the bottom is very wet in some places.
From the roadside, the ditch looks almost attractive and the vegetation is lush. It is dotted with young trees and large bushes of hawthorn that are full of red berries. In reality, the ditch is horrible. This is mainly because a large proportion of the human population are filthy and dump almost anything they feel to be inconvenient in ditches. This is a tragedy, since ditches harbour amazing plants. One of England’s rarest plants, fen ragwort (Jacobaea paludosa), has its last redoubt in a ditch sandwiched between a lorry-dominated layby and an arable field. There are chunks of broken vehicle, mainly bumpers and hubcaps. Lumps of builders’ rubble and the odd kitchen sink reflect the ditch’s history as an occasional haunt for fly-tippers. The dominant crud, however, is mountains of fast-food packaging. I start to feel pretty vicious. There is also a waft of deep foetidity, not the rich, natural compounds derived from the breakdown of leaflitter and plant matter. This pong is closer to home: it’s the urine of countless lorry drivers intermixed with human faeces. Not for the first time, I’ve just stood in someone’s crap. I sigh, proceed and thank my foresightedness in bringing my best, watertight boots. They’ll need a good scrub before I get home.
I trudge back and forth through the ditch looking for tell-tale signs of a clandestine burial. Nothing, no quick win. Sophie and I catch up with each other and decide how to proceed. The area is very large, so we’ll need to break it up into 10-metre sections before we focus our efforts. We start marking out the area with tape-measures and begin drawing our own preliminary maps. Her mapping focuses of the general landscape features, mine on the plants. I take a series of photographs to document the vegetation. We then start doing our more detailed examinations. Both of our heads are bowed as we scan back and forth, each contemplating the ground in our own way. I’m looking for signs of damage to the vegetation or plants that look odd or somehow out of their natural position. Every now and then we discuss whether we feel something arouses our interest. If so, a small flag is positioned next to something that might warrant further investigation. After we are done, the ground is festooned with small red flags. The flag positions are then plotted onto our sketch maps. Every area marked with a flag is then examined and marked off the list when we find no signs of purposeful disturbance. About an hour later, all the flags have been removed. One ten-metre square done, just another nineteen poo-infested sections of ditch bursting with bramble, nettles and thorn to examine. Time for an instant coffee and a bar of chocolate. If we need to go to the loo, we have to find a private space well away from the area or wait until the evening. Depending on the police force, it’s not very often that a portable toilet is provided.
After our quick pitstop, we proceed with examining the remaining nineteen sections. Luckily, the further we move away from middle of the layby there are fewer signs of human disturbance and it’s a lot less smelly. When we reach the twentieth, it is mid-afternoon. So far, we’ve found nothing significant. We squeeze in a late lunch − for me it’s a cheese sandwich that has been defiled with mayonnaise. Lunchtime conversation starts off with a few grumbles about aching knees but soon turns to what we’ll do next. One of the detectives has arrived, Sophie briefs him on our progress. He looks quite glum; he rather liked the look of this location and was clearly hoping for early results. We all were. There are signs of sleet on the way. We discuss what our next priorities will be.
It’s clear that some of the PolSA team are itching to do something. It’s not in their nature to sit waiting while some fey botanist from London looks at flowers. There is a suggestion that a small digger be brought in to ‘speed things up’. Sophie goes a little pale. She does this when she’s drawing on her diplomacy reserves. I sense her slight pause for breath as she calmly explains that this would not be a good idea. In my mind, I agree with her. Coming from a farming and horticultural background, I can tell when soil is carrying as much water as it can cope with. Driving heavy vehicles over saturated clay soils is asking for trouble. It will become a quagmire. The site will become horrendous and potentially dangerous to work in. Carefully, Sophie explains that heavy machinery could cause significant damage to any evidence, especially the woman’s remains. Thankfully, the idea is shelved.
The three main areas left to search are two large fields and the hedges which surround them, a small stream which is surrounded by dense thickets of very spiny blackthorn hedge and the plantation woodland. From the information provided by witnesses, the police favour the fields and hedges. The PolSA team have been on site for several days, and the lead PolSA tells us they have already ‘taken a look’ along the
hedgerow bordering the stream and dug a few pits. Once more, Sophie’s skin pales, and I can guess what’s coming next. She asks the PolSA if there are any sketch maps of where they’ve dug. There aren’t, but he claims he knows exactly where they all are. As it turns out, they are not quite so sure, and we spend some time locating all of their pits.
It would be easy to roll one’s eyes at this. But, spare a thought for the PolSA team. They’ve been crammed in the back of a police van for several days. Most of them have probably never worked a (suspected) crime scene in the countryside and, from what I’ve seen, they get very little training that would equip them for scenes such as this. Most serious crimes occur in and around the home, the street or the workplace; potential crime scenes in the countryside are rare and so police staff often don’t get much opportunity to work in places like this. From what I’ve gleaned, they’re pretty much expected to train on the job when it comes to atypical scenarios. Nevertheless, undocumented activity at a scene is not entirely helpful. Sophie and I will have to re-examine the dig sites to ensure that nothing is missed.
To get a better view of the inside of the hedge and the banks of the stream, I clamber down onto the stream bed. Despite the heavy rain of the last few days, it’s shallow in this section. The stream is quite narrow but steep-banked. It is obvious that getting the body of a murder victim down here at two in the morning would be very hard, but not impossible. Therefore, I must continue checking. After several hundred metres, my phone beeps. I take it out to check my email, because I’m also dealing with an enquiry about another murder. There’s nothing of importance and as I go to put my phone away, I stumble slightly and drop my phone in the stream. Whilst simultaneously swearing a lot my hand darts into the icy water and retrieves the phone. Amazingly, it continues to work and the PolSAs get a small laugh at my expense.
Murder Most Florid Page 7