An environmental advocacy group is paying the registration fees for Santa Cruz mayor Martine Watkins (D.) to attend the United States Conference of Mayors Summit in Hawaii later this month, where Watkins will speak in favor of governments suing large energy producers over climate change.

Santa Cruz is one of many California municipal governments that have filed nuisance complaints against companies such as Exxon, BP, and Chevron asking courts to order the creation of "abatement funds" to pay for past and future damages resulting from climate change.

Watkins told the Washington Free Beacon by email last week that the nonprofit Union of Concerned Scientists (UCS) "has offered to cover the conference registration cost on my behalf. I'm using personal funds to cover the remainder of costs."

UCS later confirmed the transaction was already completed.

In a recent editorial, Watkins told constituents no tax money was being spent on the trip, but also did not mention that UCS was playing a role in the funding.

"I’ve been invited to participate in the Climate Mayors Summit on June 26 in Honolulu as a member of a roundtable exchange, to share information about our climate action work," Watkins wrote in the local paper Santa Cruz Sentinel.

"Although I’ll be attending as the Mayor of the City of Santa Cruz, I will not be using any city funds, resources, or taxpayer dollars. I am personally committed to using this national platform to advocate on behalf of our city, and ultimately, the sustainability of our planet for future generations."

"I will specifically speak to our lawsuit against the largest fossil fuel corporations seeking to hold them accountable for their reprehensible contributions to climate change."

The UCS has agitated for exactly these kinds of legal actions.

Documents previously published by Chris Horner of conservative watchdog group Government Accountability and Oversight showed that in 2016, UCS was co-host for a "safe space" meeting at Harvard University including activists, government officials, and lawyers to discuss possible legal actions by governments against energy producers.

Another email, also obtained by Horner, showed that in 2015 UCS was already strategizing along these lines, writing that "we think there’ll likely be a strong basis for encouraging state (e.g. [attorney general]) action forward and, in that context, opportunities for climate scientists to weigh in."

UCS’s underwriting of program fees for Watkins could possibly violate California ethics laws.

According to a fact sheet published by the state’s Fair Political Practices Commission, payment of registration would likely fall under honoraria.

Honoraria are acceptable under California’s ethics rules in some circumstances such as free admission to an event where the official is making a speech, "so long as the admission is provided by the person who organizes the event." However, in this case the US Conference of Mayors, the organizers of the event, would not be the entity paying.

A part of the USCM registration packet for the Hawaii event lists registration fees ranging from $950 to $2,000.

While Watkins did respond to the Free Beacon’s original query about how funding was broken down, she did not respond to follow-up questions, including whether the proposed funding met all applicable ethical guidelines.

Watkins also mentioned in her editorial that she will co-sponsor "a resolution to be brought to the US Conference of Mayors for formal adoption, that supports cities’ rights and efforts to mitigate climate change damages and protect taxpayers from related costs."

"This includes our right to have access to the courts to resolve our dispute over climate change related damages and adaptation costs."

Thus far, courts have been reluctant to involve themselves in the controversy, at least where governments are looking for remuneration.

"A federal judge Monday tossed out two groundbreaking lawsuits by San Francisco and Oakland that sought to hold some of the world’s largest oil companies liable for climate change," the San Francisco Chronicle reported almost one year ago. "In an exhaustive, 16-page ruling that touched on such scientific matters as the ice age and early observations of carbon dioxide, U.S. District Judge William Alsup acknowledged the problem of a warming planet but said it is just too big for the courts to solve."