The Cook County Jail in Chicago is one of the largest in the country.

Sprawling across 96 acres on the Southwest Side, the facility houses more than 4,000 people, most awaiting trial. Its cramped living conditions made it a perfect petri dish for COVID-19.

Today, the jail is home to one of the largest known outbreaks in the country and has been a flashpoint in the national debate over how to contain the virus in correctional facilities. More than 9,400 cases have emerged in prisons across the U.S., according to an analysis by The Marshall Project. In the Cook County Jail, nearly 500 detainees and more than 300 correctional officers have tested positive.

Seven people have died: six inmates and one guard.

Sheriff Tom Dart is now under fire for his oversight of the jail in the era of coronavirus. In a federal lawsuit, civil rights attorneys have blamed him for failing to curtail what they have called a “rapidly escalating public health disaster,” and the judge in that case has ordered Dart to improve sanitation, to expand social distancing and to report back on his progress.