President Joe Biden's decision to send Massachusetts House Majority Leader Claire Cronin to Dublin as the new U.S. ambassador to Ireland reflects well on the State House, but replacing Cronin presents a challenge for the new Speaker Ron Mariano who entered office promising a leadership team as diverse as the chamber.

Before he was elected speaker in December, Mariano "pledged to build a leadership team that reflected the diversity of the House," according to a February press release from his office announcing his leadership picks.

"Today’s appointments fulfill that promise, making historic gains for women, people of color, and the LGBTQ community," the release read.

If Mariano sticks to his current roster of House lietentuents, the top leadership posts — none of which are currently held by Black lawmakers — could become a bit less diverse after Cronin's departure.

If Mariano chooses to fill the void left by Cronin by simply promoting his current team up one position, Speaker Pro Tempore Kate Hogan of Stow would become the chamber's first LGBTQ majority leader and the second woman in the position.

Assistant Majority Leader Michael Moran, a straight white man and key player in House politics, would be in line to take Hogan's place as Speaker Pro Tempore. Mariano has two second assistant majority leaders: Chicopee Rep. Joseph Wagner, a straight, white man, and Provincetown's Rep. Sarah Peake, who is gay.

Also part of his diversity agenda, Mariano named a record number of women to chair committees this session.

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The only person of color on Marianos' team at the moment is Lawrence Rep. Frank Moran, a Latino and the chair of the House's third division. The other three division chairs, James O'Day of West Boylston, Ruth Balser of Newton and Thomas Golden of Lowell, are all white and straight. The House has seven Black members: four women and three men.

"The most reliable voting block in the entire Democratic Party are Black people, and to not have a black person in the leadership team still does not, to me, say you have diversity," said Russell Holmes, a Democrat from Mattapan and the most senior member of color in the House.

Holmes briefly mounted a challenge to Mariano's election to the speakership and had long been on the wrong side of former Speaker Robert DeLeo, dropping from a vice chairmanship to rank-and-file status after a disagreement with DeLeo.

Holmes said one of Mariano's challenges naming new leaders will be deciding whether to promote less experienced Black and Latino members over veteran white lawmakers.

"The person who would be appropriate in his leadership team would be me, obviously, and I'm a troublemaker, and I'm sent from a district that expects me to be a troublemaker in that building," Holmes said of the State House.

Cronin, a leader on criminal justice, abortion access and police certifiaction, was nominated by Biden Thursday. She awaits confirmation by the U.S. Senate.