CHICAGO (AP) — Chicago Democrats on Wednesday chose an attorney and onetime chief of staff to former Cook County Board President Todd Stroger as their third-party candidate to challenge indicted state Rep. Derrick Smith.

The group, led by Illinois Secretary of State Jesse White, vetted several candidates in public forum-style meetings before settling on Lance Tyson, 40, who runs his own law practice. Since Smith has defied calls to step down or take his name off the November ballot, Democrats took the unusual step of creating the 10th District Unity Party to put up another Democratic candidate.

Tyson said he'd already secured support from unions to run in the district on Chicago's West Side.

"I'm incredibly humbled to have gotten an opportunity to present my ideas on the free market." he said. "It's time to roll up my sleeves and get to work."

As a third-party candidate, he will have to get 1,500 signatures to put his name on the ballot. Tyson said he is aiming for 4,000.

Smith was arrested in March and charged with taking a $7,000 bribe in exchange for helping a day care center obtain a state grant. Despite his arrest, he easily won the Democratic nomination in the March primary. The Chicago lawmaker has repeatedly denied wrongdoing and refused to resign, despite pressure from top Democratic leaders in Illinois, including White and Gov. Pat Quinn.

Smith has declined interview requests.

Nine candidates were considered by the committee, which narrowed it down to three before Wednesday's meeting. But questions about the process were raised Tuesday when it was revealed that one of the three remaining candidates, insurance manager Melissa Conyears, is the girlfriend of Alderman Jason Ervin. He's on the committee.

Ervin disclosed the fact in closed session, according to committee members, but he did not discuss it in public proceedings. White has said that he wanted an open selection process.

Ervin said Wednesday that he believed his relationship with Conyears cost her the committee's support.

"I have no issue with my relationship. I don't think that should have been a factor in determining who a candidate is, I think the credentials for the candidate speak for themselves," he said. "I did not hide the fact of our situation. I'm disappointed that the committee couldn't get beyond one point."

Conyears declined to speak of the relationship, saying only that she had top-notch qualifications. The third finalist was Chicago police officer Eddie Winters. Nothing prevents either candidate from deciding to run on their own.

During the meetings, Tyson touted his work experience: He worked as legislative counsel for former Chicago Mayor Richard Daley for five years before he became Stroger's chief of staff from 2006 to 2008.

The ties to Stroger, who left office in 2010, are likely to be brought up on the campaign trail.

His administration was plagued with allegations of political corruption and ethical lapses, starting with how he got the job. His father, the late John Stroger, held the job for a dozen years and when he suffered a stroke in 2006, he had Democratic insiders place his son on the ballot. Stroger also faced major public backlash after he proposed to raise the county portion of the sales tax by 1 percentage point.

Tyson told the committee that he resigned from Stroger's administration after less than two years because his interests diverged from Stroger's.

When asked how he would address the links to Stroger on the campaign trail, Tyson only played up what he learned on the job.

"As I said before, I am incredibly honored to have had an opportunity to serve the taxpayers of Cook County, certainly a lot of tumultuous times we went through there," he said. "We accomplished a lot."