CIO Jason DeHaan has left the city government, multiple sources have confirmed to Government Technology.

DeHaan was appointed CIO in November 2010, six months before Mayor Rahm Emanuel took office. DeHaan came up through the city ranks, having previously served as Chicago’s deputy CIO for three years, according to his LinkedIn profile.

DeHaan, pictured at left, was in charge of the city’s internal IT operations, while Chicago’s digital trio — CTO John Tolva, Chief Data Officer Brett Goldstein and Director of Social Media Kevin Hauswirth — manage innovation and citizen-facing projects.

DeHaan did not immediately return a phone call seeking comment on Friday, June 1.

In addition to his public-sector experience, DeHaan has approximately 10 years in private-sector positions. He was chief technology officer of ieLogic, a start-up Internet poker software development company from 2001-2005 and prior to that was a manager with Accenture’s Global Retail Practice.

DeHaan, who holds an MBA from Northwestern University’s Kellogg School of Management and a bachelor’s degree in finance from the University of Illinois at Urbana-Champaign, also worked as manager of onsite consulting for his undergraduate alma mater, where he helped computerize the class registration system for 40,000 students, faculty and staff.

Mobile technology was one of the highlights of DeHaan’s tenure in Chicago. In 2010, prior to assuming the city’s CIO post, Government Technology Editor Steve Towns spoke to DeHaan about a smartphone application that Chicago ward supervisors were using to clean up the city.

In an interview in GOVERNING — a sister publication of Government Technology — DeHaan explained that by automating inspection processes through the use of an app, Chicago saw a huge uptick in citations issued to owners of trash-strewn vacant lots. The paper-based manual system that was used previously didn’t get the job done efficiently.

“They simply couldn’t take the time to do that for every violation, so they let some go,” DeHaan told GOVERNING. “We saw a tremendous increase in ticketing when we deployed the application, and I attribute that largely to the convenience of the mobile device.”