Two weeks ago, Boston tourism chief Kenneth Brissette was indicted by a grand jury on a charge of extortion—namely, using his office to pressure the Boston Calling festival into hiring union labor that the company neither wanted nor needed. Brissette has pleaded not guilty.

The charge was the latest tremor in an unfolding scandal that has shaken Boston’s City Hall since The Boston Globe reported in April that at least one grand jury had been assembled in a probe of union-related wrong doing.

The federal indictment of Brissette focuses specifically on his dealings with Boston Calling organizers.

But city emails obtained through a public information request by WGBH News suggest that officials other than just Brissette were being apprised of hiring practices for local events—and not just for Boston Calling.

In August 2014, Brissette forwarded multiple emails regarding Enlighten, a proposed lighting exhibit by AGB Productions, an Australian production company, that wanted to put on the exhibit as part of Boston’s First Night New Year's celebration.

On August 20, 2014, Brissette replied to an email from a marketing consultant for the Enlighten project, asking, “Can you let me know who the local people are that will be working on this?”

The email was blind copied to Timothy Sullivan, chief of staff for the city’s Department of Intergovernmental Affairs and a former AFL-CIO director.

A response saying that the production intended to hire, among other workers, “4 IATSE Local 11 stage hands for set up and tear down of equipment,” was forwarded from Brissette to Sullivan an hour later, with Brissette adding only, “FYI.”

IATSE, the International Association of Theatrical Stage Employees, is the same union local mentioned in the federal indictment of Brissette.

Brissette also exchanged emails with Sullivan about a meeting regarding Boston Calling in September 2014, shortly before the company agreed to hire members of International Alliance of Theatrical Stage Employees, as the Globe reported this weekend—though WGBH News did not find any explicit mention of union labor in those emails.

Neither Brissette nor Sullivan responded to an immediate request for comment. Susan Chavez, the consultant corresponding with Brissette on behalf of the production company, declined to comment when reached by phone on Sunday.

Laura Oggeri, a spokesperson for Mayor Marty Walsh, responded to related questions from WGBH News by email saying that “Mayor Walsh has asked Attorney Brian Kelly to look into Boston Calling and the city's interactions with the event, as well as the tourism department as a whole, to answer these questions and ensure that the proper procedures are in place.”