Private Investigator


From Las Vegas to New York to Bow Valley College

Students learn from the P.I.s who’ve fascinated an international audience.

It started in 1988 when a mutual friend told Marnie Milot and Ali Wirsche that she thought her husband was having an affair. “We put our heads together and decided if she could babysit all our kids, we would track him for her,” said Ali in a 2012 article in the Globe and Mail.  

After tracking him for months, they caught him. 

“And then another friend called,” says Ali.  

Marnie had been working as an administrative assistant, but became fascinated with private investigating when she met a P.I. while living in Greece in the 1970s. Ali had been working as an interior decorator for 13 years, but as a girl dreamed of becoming a police officer (or a famous singer). When they quickly started getting cases, it was clear: they could make a go at this full-time. 

The two Calgary women got their licences from Alberta Justice and opened Backtrack Investigations, their P.I. business, in 1995. Marnie was 45 and Ali was 40. They specialized in infidelity and other domestic cases and worked for lawyers and insurance companies, where they did surveillance and gathered information on people claiming they were injured in accidents. A Calgary Sun article reported that a husband Marnie and Ali had caught cheating on his wife was so impressed, he later hired them to track his girlfriend he suspected of cheating. 

In 1998, Marnie and Ali published their first book, Gotcha!!!: How to Tell if your Lover is Having an Affair, following it up with Sex, Lies and P.I.s in 2005. They have earned attention across North America in newspapers and magazines and on television and the radio. In 1998, they made their first of three appearances on the Sally Jessy Raphael Show in New York. “They contacted us because they saw our book,” says Ali. 

They have also appeared on the Wise Guy Show, live at the Golden Nugget Casino in Las Vegas. 

Marnie and Ali have since sold their business, but in 2004, they were approached by Bow Valley College to develop and teach the Private Investigation Certificate. The program includes six courses, which focus on techniques like interviewing, surveillance, and report writing, as well as operating undercover and starting your own business. Offered online, it is available to students who live in Calgary and beyond.    

James Garrow took the courses from his home in rural Saskatchewan. “Being able to do online courses was key,” he says in an article on “The instructors really helped me get into it and coached me along the way. Even though it was online, they were always actively engaged, making the whole experience great.”

Ali says that she loved the in-class interaction, but online learning is so much easier for the students and the instructors. “I feel it is more one-on-one,” she says. “And with the way the discussions are structured, the students interact.” 

She also enjoys that she can mark an assignment or reply to a discussion on her schedule. With that well-earned flexibility, Marnie and Ali can spend time other interests of theirs – for Marnie, it’s cooking, travelling, and the Toronto Blue Jays, and for Ali, it’s interior design, playing golf, and gardening.   

Start sleuthing as early as April 3! To register for Introduction to Private Investigation, the first course of the certificate, or to see alternate start dates, visit the course page

Posted on March 27, 2019

Story by Julie-Anne Cleyn

Your cart is currently empty.

Browse Available Courses


  • If you are currently studying in a post-secondary program at BVC, please register for your courses via mybvc to ensure your enrolments and fees are processed appropriately.
  • Cart total based on domestic tuition rates. For information about International Tuition rates please see Additional Fees Apply
  • If you anticipate applying for a student loan, your payment will be refunded to you based on your loan award once your funding has been received by BVC.

We use cookies to ensure that we give you the best experience on our website. Learn more in our privacy policy