At last it can be revealed: Ronald D. Castille is monitoring courtroom manners.

On Wednesday, a day after the retired Pennsylvania Supreme Court justice confirmed that he was consulting for the defense in the civil trial in the deadly 2013 Center City building collapse, veteran Philadelphia lawyer Richard A. Sprague disclosed Castille's mission.

As the 91-year-old Sprague told Philadelphia Common Pleas Court Judge M. Teresa Sarmina - without the jury present - he contacted Castille after the Nov. 23 session, when plaintiffs' lawyer Robert J. Mongeluzzi was vigorously questioning Thomas J. Simmonds.

Sprague and his firm represent New York real estate speculator Richard Basciano - another 91-year-old - and his STB Investments Corp., which owned a vacant four-story building being demolished.

On June 5, 2013, an unsupported three- to four-story wall remaining from the Hoagie City building toppled and destroyed a Salvation Army thrift store next door at 22nd and Market Streets, killing six people and injuring 13.

Simmonds, 54, was Basciano's property manager and deeply involved with the demolition project. Mongeluzzi honed his take-no-prisoners interrogation style to try to show the jury that Simmonds - and by extension, Basciano - deserves to be held liable.

After testimony ended Nov. 23, Sprague told the judge he was outraged by Mongeluzzi's "yelling and screaming at this witness."

Sprague then demanded that Mongeluzzi's cross-examination of Simmonds be audio-recorded so an appeals court could hear the tone and decibel level.

Mongeluzzi denied screaming, saying he had raised his voice because Simmonds was not properly responding to his questions.

Sarmina noted Sprague's objection but denied his call for a recording, which apparently prompted Castille's appearance Tuesday when the trial resumed after the Thanksgiving break.

On Wednesday, Sprague explained what he had done, and called Mongeluzzi a "dear friend" whose professionalism was beyond reproach.

Sprague then recited court rules about treating witnesses "with fairness and consideration. . . . They should not be harassed or unduly embarrassed."

Acknowledging that he had expressed "incredulity" about Simmonds' testimony, Mongeluzzi said that neither he nor the other plaintiffs' lawyers had "embarrassed" Simmonds.

"If they were embarrassed about him being demolished by our questioning, nobody embarrassed him. They embarrassed themselves," Mongeluzzi added.

Simmonds remained on the witness stand Wednesday, being questioned by a lawyer for the Salvation Army. He is to return Friday. Thursday's session was canceled because the judge had a previously scheduled criminal case hearing.

The plaintiffs' lawyers maintain that Basciano and Simmonds should be held liable because they did no research before hiring an architect and demolition contractor for the ill-fated project.

Simmonds has blamed Center City architect Plato A. Marinakos Jr., whom he hired as STB's agent monitoring demolition.

Simmonds insisted he did not have the knowledge to ask informed questions about the demolition.

According to trial testimony, neither Marinakos nor Campbell had experience demolishing a multistory commercial building in a downtown environment.

In addition to Basciano and STB, those being sued include Marinakos, Campbell, and excavator operator Sean Benschop.

The Salvation Army is being sued for purportedly ignoring the growing danger at the demolition site next door and allegedly failing to warn store employees and customers.

215-854-2985 @joeslobo