Massachusetts Democratic Party Chairman Gus Bickford was one of the 17 members of the Democratic National Committee’s resolution committee who voted not to hold a DNC-sponsored presidential debate about climate change. Bickford’s "no" vote at the DNC’s meeting in San Francisco Thursday came two weeks after the Massachusetts Democratic State Committee unanimously voted to call on the DNC to sponsor a debate about climate change.

In a statement provided to WGBH News, Bickford defended his decision and said he voted against the resolution because it would have altered the rules for the presidential debates established by the DNC last year, which he said all of the candidates signed onto.

“The proposed resolution that we considered yesterday would have had a significant impact on the debate process and was not primarily about the climate change debate. This resolution had a friendly amendment added which would throw out the current rules for our Democratic presidential debates,” Bickford said. “I, and other members on the resolutions committee, did not believe the current rules should be changed in mid-process.”

Climate activists have criticized the DNC's decision. The Sunrise Movement, a national movement of predominantly young activists who have advocated for bold climate change reforms like the Green New Deal, said they were not disheartened by the vote and planned to continue to pressure DNC Chair Tom Perez to hold a debate.

“In the coming days and months, we’ll keep fighting to make sure the DNC and Tom Perez treat the climate crisis like the emergency that it is, and allow it the airtime and attention that it deserves,” Garret Blad, national press director for the Sunrise Movement said in a statement.

Sen. Ed Markey also weighed in on the decision. Markey, who introduced the Green New Deal resolution in the Senate and was recently endorsed by the Sunrise Movement, said that activists should continue to pressure the DNC to hold a debate.

“There should be a debate on climate at the DNC,” Markey told WGBH News. “We should take this issue and put it right out in front. We should lean in on the issue. We should not back up at all.”

Presidential candidate and Sen. Elizabeth Warren has also supported the idea of a DNC-sponsored climate debate. In a tweet on Thursday, Warren called climate change an “existential threat.”

CNN will hold a climate change forum on Sep. 4 that will feature eight presidential candidates, but it will not be done in partnership with the DNC.