It was inevitable that internal tension would surface this year between Assemblyman Das Williams of Santa Barbara, a close ally of former Assemblywoman Hannah-Beth Jackson, and Assemblywoman Fiona Ma of San Francisco, the newly wed wife of Oxnard Harbor District Commissioner Jason Hodge.

The reason: Jackson and Hodge, both Democrats, are running against each other in the 19th Senate District primary.

It took only a week for that tension to flare. On Jan. 11 a bill authored by Williams designed to speed the process through which state regulators establish control measures for the use of chemicals in pesticides that have been determined to be "toxic air contaminants" was defeated. It was voted down in the Assembly Agricultural Committee, in part because Ma voted against it.

Williams notes that the bill, which had been defeated last year in the same committee, had been substantially watered down to meet the concerns of agricultural industry opponents that it would have placed an unreasonable timetable on the scientific review of pesticides. A committee analysis shows that the 2011 opposition from the California Farm Bureau Federation, the Western Growers Association, California Citrus Mutual and others had been removed as a result of the changes.

He asserts that Ma's opposition -- a relatively rare phenomenon of a Democrat voting against another Democrat's bill in policy committee -- was motivated by the politics of the Senate campaign. He told me last week that he thought it was beyond the pale for Ma to cast a politically tainted vote against a bill supported by environmental and farm worker advocacy groups across the state, including Ventura County's Central Coast Allliance United for a Sustainable Economy (CAUSE).

Ma told me today that Williams' allegations are off base. She noted that she did not vote for the bill in committee last year (she abstained then), that she based her vote on the belief that the Department of Pesticide Regulation is already working as quickly as it can to evaluate the chemicals, and that the committee's Democratic chairwoman, Cathleen Galgiani , also voted against the bill.

She also pointed out that a different Williams bill, one that would have imposed restrictions on trucks using Highway 33, had been voted down in the Assembly Transportation Commission that same week as a result of Democratic opposition.

"For him to say Democrats never vote against Democrats is totally wrong," Ma told me. "He cries foul, but it's not truthful."