Sylvie Therrien told CBC News that she and other investigators were given a target to recover nearly $500,000 in EI benefits every year.
"It just was against my values, harassing claimants… trying to penalize them in order to save money for the government. We had quotas to meet every month," Therrien said.
Therrien leaked documents to the media anonymously in the spring showing investigators were ordered to find $485,000 in savings each year by denying claims.
The federal government denied that any quotas were in place, but the opposition hammered the Conservatives on the issue.
"Telling investigators that they each had to find half a million in fraud presumes that there is widespread fraud, that they're all a bunch of cheaters and criminals," said NDP Leader Thomas Mulcair in the House of Commons in February.
EI investigators were then called in for questioning themselves to find out who leaked the document.
"Witchhunt terminology. It definitely describes what was happening," said Don Rogers, national president of the Canada Employment and Immigration Union.
"They were trying to find out who had told the media that there were targets to be achieved."
Therrien was questioned by investigators in May. She admitted she was the source of the leak and was suspended without pay.
"I knew my job was in peril. I knew that, but I couldn't continue. I couldn't sleep," she said.
"I was thinking just about those people… I was going to send them and their children into the street… and now here I am on the street."
Therrien suspects she will be fired, but hopes her union and lawyer will back her up in court.
Human Resources Canada would not give any details about Therrien's case. But in a statement, it says all Service Canada employees are bound by a declaration not to go public with government information.