The mortgage loan application process can be daunting, and Linda Weekes knows all too well that there are always applicants and brokers looking to skirt the rules to get the deal they want.

As a former senior mortgage underwriter and early whistleblower at the Lehman Brothers subsidiary BNC in 2005, Weekes tried to bring attention to the behaviors that partly contributed to the collapse of the housing market.

“I’ve been in the mortgage and banking industry for 48 years. I worked for BNC, which was a subsidiary of Lehman Brothers, and through the process of working for them and discovering fraud, I was retaliated against,” Weekes tells Yahoo Finance.

Weekes finally has the chance to tell her side of the story through Jennifer Deschamps’ new documentary “Inside Lehman Brothers,” which premiered at the DOC NYC film festival this month. “Lehman Brothers were all about money, and they didn’t care how it came and at whose price and sacrifice. It did not matter to them, and I just wasn’t on board with that.”

“As a mortgage loan underwriter, it’s our job to make sure that, No. 1, we’re protecting the company and No. 2, we’re protecting the prospective homeowner,” she explains. “It’s important to me that the homeowner is able to sustain that home for the term that they have signed up for.”

Weekes’ work involves a studied attention to detail and an almost cynical approach to human behavior, assuming every mortgage loan application is full of lies until it can be proven otherwise. “I have a sense. I can tell when things are not adding up, and I know what to look for,” she says. “It’s my job to make sure that it all matches up, and it’s my job to make sure that my company is making good loans, not fraudulent loans.”

That level of detective work is necessary because dishonesty in the mortgage loan application process is still very common. For prospective homeowners looking to navigate the mortgage loan application process smoothly, Weekes offers some sound advice.

Don’t lie… and watch out for brokers who do

“You should tell the truth and provide all accurate documentation without it being doctored,” Weekes says. “Fill out the mortgage loan application accurately, and provide the supporting documentation.”

While being honest may seem like pretty straightforward advice, applicants might run into mortgage brokers looking to persuade them into bending the truth. For that reason, Weekes recommends standing your ground.

“You should not falsify anything, nor should you allow a loan officer or anyone to talk you into doing something that you know is not accurate,” she says. “It’s a federal document, the mortgage loan application. You are supposed to complete that mortgage loan application with all accurate, factual information. If somebody is telling you, ‘Don’t put that, put this,’ and you know that that’s not correct because you know your own history, then you shouldn’t follow that direction.”