A top Chicago Public Schools official is expected back on the stand Thursday morning. Dr. Markay Winston was the first witness for the Chicago Board of Education, which started presenting evidence late Wednesday afternoon. The testimony is part of a hearing before Federal Court Judge John Lee, who will decide whether the planned closure of 49 Chicago elementary schools violates federal law protecting kids with disabilities. The closures are already well underway but attorneys representing kids are hoping their federal lawsuit will slow down, or even stop the closures.

Winston is a top CPS administrator and a member of CPS CEO Barbara Byrd-Bennett’s cabinet. Winston made a strong case for school closures, saying they will result in a more efficient system that serves kids better.

But Winston undermined that case when, under cross-examination, she refused to concede seemingly obvious points. Rather than give straight answers, she obfuscated or said she didn’t understand questions. After Winston repeatedly refused to answer a yes or no question from a lawyer for students affected by the closures, federal Judge John Lee instructed her to answer either yes or no.

Winston dismissed the judge’s instruction and persisted in her refusal, saying she couldn’t answer with a simple yes or no.

The evidentiary hearing began Tuesday. Each side has been allotted 10 hours to make its case to Judge Lee. According to Lee, who is acting as the timekeeper, as of Wednesday night the plaintiffs’ lawyers had two hours and 55 minutes of time left. Attorneys for the school board, who just started presenting their evidence, have eight hours and four minutes.

Judge Lee is hearing testimony to help him decide if he should order a preliminary injunction halting the closure of about the 49 elementary schools.

Attorneys for parents seeking the injunction before the new school year starts called the first witnesses Tuesday.

In testimony that day, education professor Pauline Lipman told Judge John Lee that the closings in the nation’s third-largest school district inordinately impact African-Americans.

She says 87 percent of students affected are black, while blacks comprise just 40 percent of overall students.

Lipman says the closure of 50 schools in a single year in one school district is unprecedented nationally. And she says the consequences aren’t clearly known.

City officials say the school buildings were underused and closing them will save millions.

The hearing is expected to conclude Friday.