INDIANAPOLIS (CBS) — Two reports are out on the collapse of the stage at last summer’s Indiana State Fair, and the response to the disaster, in which seven people died and dozens were hurt.

As WBBM Newsradio’s Bob Roberts reports, Chicago-based engineering firm Thornton Tomasetti determined that the rigging in use on Aug. 13 of last year could withstand winds of 25 to 40 mph, but nothing close to the 59 mph gusts that night – let alone stiffer state code requirements.

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LISTEN: WBBM Newsradio’s Bob Roberts reports

The firm found that the stage’s roof tarp helped prompt the collapse.

In a separate report, Washington-based Witt Associates found that the Indiana State Fair Commission lacked formal protocols to delay, postpone or cancel concerts, and also suffered from communication problems. Overall, Witt said in its report, the commission was not adequately prepared.

Witt recommends that the commission develop a comprehensive emergency preparedness plan for year-round operations.

On Friday, the band Sugarland was expected to testify before Indiana state safety regulators, as they try to determine what caused the collapse.

Lead singed Jennifer Nettles said she did not know she had the option to cancel the concert because of the weather.

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But Indiana attorney Ken Allen, who represents injured survivors of the stage collapse, says Nettles in a deposition this week indicated the band declined to cancel the show when asked.

“In her deposition, Jennifer Nettles said that the safety of her fans was not her concern,” Allen said at a Friday news conference with injured concert-goer Beth Urshel.

On the night of the collapse, concert-goers said opening act Sara Bareilles had finished performing, and the crowd was waiting for Sugarland to take the stage when the storm hit just before 9 p.m.

Meteorologists believe the wind storm might have been what’s known as a “gustnado” — which forms when a strong wind just before a thunderstorm causes the air to circulate like a tornado.

A Chicago woman was among those killed. Christina Santiago, 29, of the Edgewater neighborhood, managed programming at the Lesbian Community Care Project at Howard Brown Health Center in Chicago.

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Santiago’s partner, Alisha Brennon, later filed lawsuits in connection with the incident, requesting damages and spousal death benefits from the State of Indiana.