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A day in the life of a private investigator

BY Juliane Schiemenz

17th Jul 2023 Life

A day in the life of a private investigator

A husband with a whip in his car. A con man eyeing an elderly woman’s wealth. It’s all in a day’s work for Louisa Erismann, private detective

A blonde woman in her mid-60s walks through an exclusive Zurich neighbourhood. Well-groomed and slender, she is wearing a dark quilted jacket, black jeans, stylish but inconspicuous sneakers, discreet jewellery and fashionable glasses. She doesn’t particularly stand out. People her age tend to fade into the background.

She smiles as she squints into the sun. Traces of a curious, sassy girl can be seen in her face—a girl who is pleased because no one can find her during a game of hide-and-seek. Her expression seems to say, If they only knew! The woman’s name is Louisa Erismann, and she has been a private investigator for the past six years. I’ll be accompanying her for the next week as she does her investigative work.

“Great that you’re coming along with me!” Erismann whispers as we walk together through the residential area. “Two people together are less noticeable. And who would ever suspect they’re being staked out by two women?”

We’re doing what’s called reconnaissance. Casing a place. I learned that from reading the books Guide to Surveillance and Profession: Detective, which Erismann gave me to help me prepare for our week together. She advised me on the kind of clothes and shoes to wear; I, too, am in dark colours.

Today’s reconnaissance involves a dispute between a man and his female neighbour. I am not permitted to share all of the details about this or any other assignments mentioned in this article. But this much I can say: Erismann has been hired to watch the neighbour.

The Swiss Miss Marple

Eirsmann completed a one-year vocational training program in private investigating, which cost her about 8,000 euros, at a school in Zurich. For her assignments she studies the target’s daily routine, then puts him or her under observation. She’ll watch them at 5am, again at noon, then in the afternoon. Sometimes stakeouts take up to 15 hours.

In her unremarkable car Erismann keeps a pair of binoculars, and jackets, toques and scarves with which she can quickly disguise herself; they also help her stay warm during long periods of surveillance. There are shopping bags in the trunk, so she can open it and make it appear as if she just came from the supermarket. Her detective kit also includes wigs, a change of shoes, thermal underwear, vitamins and bananas.

In her office she has manuals on surveillance methods and forensics, along with a copy of the Swiss Civil Code. Erismann always obeys the law when conducting her investigations, and respects the privacy not only of her clients but also of the people she investigates. “Once, a client wanted me to record a video through a keyhole. That is prohibited, and I won’t do it. In proper surveillance work, you don’t have to violate people’s privacy.”

Stake out in car

A lot of detective work goes on in cars

Once, she signed up as a guest at a Tupperware party because she was surveilling the host. Another time she was hired by a filmmaker who desperately wanted to buy a mansion, so she tracked down its owners. On another occasion, she was assigned to watch a woman who had been on sick leave for more than a year due to a broken foot; Erismann discovered an up-to-date photo on social media of the woman walking her dogs.

Erismann always has several cases on the go. A recent one involved a lawyer who disappeared once a month. His wife had no idea where he was going, but then she discovered that one of his Viagra pills was missing. The wife hired Erismann, who followed his trail to Germany, where she found he was frequenting various hotels. In the wheel well of his car, she discovered a bag containing a whip and other sado-masochistic paraphernalia.

Indeed, Erismann mostly investigates wealthy men suspected by their wives of cheating; about two-thirds of her clients are women. “In my experience,” says Erismann, “if a spouse suspects something is going on, they are usually right.” Only once in her professional career has a suspicion of infidelity proved unfounded.

"Erismann does the reconnaissance work and takes the photos, then delivers the bad news"

“Wives wait until they can’t bear their suspicions any longer,” she says. “They don’t want to believe it. And some don’t figure out that their partner is cheating until they get an STD.” Erismann’s cases often include gathering evidence of infidelity, which can be used to substantiate financial and custody-related claims in the event of a divorce.

Erismann does the reconnaissance work and takes the photos, then delivers the bad news. The emotionally charged nature of her assignments quickly creates a friendly, even maternal, bond with her clients. Sometimes, she later accompanies them to court, not only for divorce hearings but also for cases of alleged stalking or rape.

In one case, a lawyer hired Erismann because his elderly mother was at risk of being defrauded. A German man had weaseled his way into the mother’s heart and wallet; she had already given him more than 100,000 euros. Her son told Erismann he thought she was going to change her will to include the man. The son didn’t want to stand by and watch his inheritance disappear.

But his mother refused to share the suspected con man’s identity with him, so Erismann followed him. She discovered that this wasn’t his first scam: He’d assisted other wealthy seniors with their tax returns and financial transactions so he could obtain their credit card and bank information. Erismann took photographs of relevant account statements sitting on his car’s dashboard, and forwarded the evidence to her client. He was able to convince his mother not to change her will.

A late-life career change

Erismann does most of her work from her car, but she also has a small office in Seefeld, one of Zurich’s priciest districts. It looks nothing like those smoky film noir detectives’ agencies, with light streaming in through slanted blinds. Instead, it has a desk, chair, computer, telephone, files and law books. No plants, no personal touches. There is a meeting room with a long table, metal chairs and a flip chart. “People come to see me because this is a good address,” says Erismann. “If I were somewhere else no one would notice me.”

Before setting up her one-woman detective agency, Erismann worked for 20 years in sales at a large German optometry group. Before that, she and her then-husband owned a photography and optometry store. Erismann had trained as a photographer, taking photos at events, company parties and weddings, and became skilled at close observation and taking photos when her subjects were being themselves and not paying attention to her.

Louisa Erismann private investigator

Louisa Erismann at work

Then, two painful events led her to the profession that she took up at an age when most people are thinking about retirement. The first was 12 years ago, when Erismann tailed her own boyfriend “because I couldn’t trust him anymore,” she recalls. “I had asked him many times if there was another woman, and he always said no. But I could tell by his facial expressions, by how he answered, that something wasn’t right. I said to myself, ‘No more questions. Time to make a plan.’"

So she set up camp in a cornfield that gave her a sightline to his home and observed it from a Saturday morning until the next afternoon. She wore black to camouflage herself, and brought along binoculars, a camera and a notepad.

Her thoughts tormented her. “If you think someone is cheating on you, it’s horrible,” she says. “That’s why I understand my female clients. There’s this awful self-doubt: What did I do wrong? Why am I not enough anymore?” There in the cornfield, Erismann felt torn. “I thought, What I’m doing here isn’t fair. But on the other hand, I wanted to find out, even if it was going to be bad.” Erismann discovered the truth: Her partner was indeed seeing another woman.

The second big shock in Erismann’s life was her youngest brother’s murder at the age of 40. She doesn’t like to talk about it, saying only that she helped solve the crime. She and her family suspected who the killer was, and that it had been a contract killing. It was her only murder investigation, but it proved to be a turning point: Erismann wanted to become a detective.

Hiding in plain sight

When we arrive in a labyrinth of semi-detached houses, we walk to the one where the woman in the dispute with her neighbour lives. Suddenly Erismann whispers: “Someone’s coming.” I want to turn around, but have been told that it would make us look suspicious. A man crosses our path, looking at us. The last thing we want is for him to question our presence. We talk loudly about buying a house and how convenient it would be to have a playground right outside the front door.

Next, we reconnoitre the thrift store where the woman works. I enter first, but I’m not sure of the plan; do Erismann and I know each other or not? The target asks me if I need any help; I tell her I’m looking for a poncho. As I browse, I see that Erismann is also pretending to be a customer. Wearing a bright red hat, she poses in front of a mirror.

Erismann comes over and tells me that I should try on the fringed poncho. Ah…so we do know each other! I play along and put on the poncho. The target looks at me, then busies herself with another customer. These stakeouts, as banal as they sometimes seem, help Erismann get a feel for the people involved in a case.

"Erismann has a penchant for acting"

After a few minutes, I leave the store and head for the car, but Erismann waves me off. Never go straight to your car, she tells me later, because someone could be watching, and maybe noting the plate number. Once a detective’s vehicle has been “made,” the only option is to change to another one.

Erismann has a penchant for acting. When she is surveilling residential areas, she takes a leash with her. “If anyone asks me what I’m doing on their property, I say I’m just looking for my lost dog.” Having received threats during investigations, she always carries pepper spray.

She hasn’t had a vacation in six years. And her personal life? “I’m always busy—what man would put up with that?” Erismann shows me photos on her phone of her cats, Fellini and Flash. “It’s nice to come home and they’re both there. They cuddle my hurts away. Humans can be quite cruel.”

So has her view of love and relationships changed because of her work? No, says Erismann. She doesn’t like to think in terms of victims and perpetrators in cases involving infidelity. “Both sides have a part in the failure or success of a relationship.” Nevertheless, she spends hours comforting clients, recommending lawyers and giving practical advice such as the need to copy records of the husband’s assets.

Collecting evidence 

The next day we are back on “recce,” as Erismann calls it, and this time it’s about a custody battle. We’re in a middle-class suburb of Basel, with its apartment buildings, garages and gravel-covered backyards. A man has hired Erismann to follow his ex-wife. He claims she treats their children badly, often leaving them at home alone. He says she makes him pay full alimony despite the fact that she works as a housecleaner. She also claims not to own a car, but Erismann discovers that she does have one.

We keep a lookout for the younger son at his school, until Erismann recognizes him by his backpack; she has been told it has a green dinosaur on it. We follow the boy to his front door. He rings the bell, but no one answers, so he crosses the street to a playground and sits on a railing. A while later, the mother arrives, and she and the son enter the apartment.

Erismann and I sit on a wall across from the house and pretend to talk. After about 10 minutes, mother and child appear on the balcony. Erismann signals to me that the mother has noticed us, so we walk to the entrance of the next building, where we can’t be seen.

“In moments when I have to take cover, I sometimes get a huge adrenaline rush,” says Erismann. She’s proud of the fact that she’s never been busted while investigating a case.

"For a second round of surveillance, she puts on a hat and wears a different jacket"

We take the long way back to the car and pass a bus stop. Erismann sees a teaching opportunity: “What would I do if I was on a stakeout nearby and someone spotted me?” She sits down in the bus shelter and assumes the air of an innocent passerby. “I wait for the bus.” A few times she has had to jump on a bus or tram to maintain her cover.

Back in the car, we settle in to watch the woman’s apartment. Erismann looks out for residents who might be watching us. “Old folks behind sheer curtains are the most dangerous,” she says.

When the mother leaves with two children, Erismann takes pictures and contacts the father. Then she decides to do another round of surveillance alone on foot, since we may have already been seen together. She pulls her hair into a ponytail and puts on a hat and a different jacket. “Call me as soon as they return,” she says.

I peer through the car windows. It’s 1:45pm and drizzling. A cyclist passes. Two boys walk by on their way to the playground. I stare at the raindrops on the window. I’m not allowed to look at my cellphone; I could miss something.

But nothing happens, and about 15 minutes after she leaves, Erismann swings open the car door. We decide to break off for the day and head back to Zurich. On rainy days like this, when people aren’t coming and going, Erismann typically does her paperwork: reports, photos, files.


A rainy day is a good time to get some paperwork done

That evening I leaf through the detective books again, which also contain ads: One is for a ballpoint pen with a spy camera and built-in microphone; another features “search gloves.” The ads promise the sort of thrill that this afternoon did not deliver.

Sitting in a car for hours, waiting, watching, taking pictures. Disappearing into the background, far from the excitement and drama of private-eye movies and novels. Is that the daily routine of a detective?

And yet there is something Erismann has in common with those famous fictional detectives: They are non-conformists whose curiosity leads them to the truth. That is what drives her, too. Her lifestyle is unconventional and she is interested in human nature. In a world focused on youth and beauty, on those who stand out, Louisa Erismann knows that staying in the background is an excellent place from which to observe.

Reportagen (May, 2021), Copyright © 2021 by Reportagen

Cover illustration by Tom Ralston

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