Political consultant Jesus Cardenas has agreed to pay $5,000 to settle allegations that he violated San Diego ethics rules when he participated in lobbying contacts as a city official after accepting money from a lobbyist representing a cannabis business.

The fine is the largest penalty the San Diego Ethics Commission could impose, based on when the violation occurred. The rules have subsequently been amended to boost monetary fines to $15,000 per violation.

Cardenas ran his political consulting business, Grassroots Resources, while also serving as chief of staff to City Councilmember Stephen Whitburn, The San Diego Union-Tribune reported in 2022.

Whitburn defended the arrangement for months before later seeking and receiving Cardenas’s resignation in 2023. He did not immediately respond on Friday to a request for comment on the Ethics Commission fine.

According to the stipulation, Cardenas took meetings with Grassroots Resources client Blue Water Government Affairs in 2021, months after publicly disclosing that the lobbying firm paid him more than $10,000 for political consulting work.

City ethics rules require public officials to wait at least 12 months to participate in lobbyist contacts with former clients.

The settlement also notes that Whitburn’s office proposed amendments to the city’s municipal code while Cardenas was the council member’s top assistant — and Cardenas attended official city meetings related to the proposed changes.

“Between July 1, 2021 and September 30, 2021, Blue Water directly lobbied Respondent regarding “(u)pdates to city of San Diego commercial cannabis ordinances,” the stipulation says. “Blue Water reported receiving $2,000 for participating in this lobbying effort.”

California law prohibits city officials from participating in public policy decisions if it can be reasonably foreseen that the decision may have a material financial effect on any person or business that has paid the official $500 or more over the previous 12 months, the Ethics Commission said.

“A public official participates in a governmental decision if the official provides information, an opinion or a recommendation to affect the decision without significant intervening substantive review,” the agreement says.

The stipulation notes that Cardenas formed Grassroots Resources in 2016 and remained its top executive until 2023, according to the most recent state filings.

The company was suspended by the California secretary of state for failing to pay taxes; Cardenas said he fell behind in payments and was working to get the firm formally reinstated.

But the company ran into other trouble when it continued to do business even while it was barred from doing so due to the state suspension.

Whitburn sought and received Cardenas’s resignation in the wake of that report.

Grassroots Resources, which also employed Cardenas’s sister, then-Chula Vista Councilmember Andrea Cardenas, was involved in illegally collecting money from a federal COVID-19 pandemic stimulus program.

The brother and sister were indicted in 2023 on theft charges for collecting federal relief payments of some $170,000 to support who they said were dozens of Grassroots Resources employees.

They denied doing anything wrong, even though Andrea Cardenas had filed paperwork with the city of Chula Vista indicating that the company had no employees.

The first-term Chula Vista elected official also pledged to seek re-election in 2024.

But in early 2024, the defendants both changed their minds and pleaded guilty to a single felony charge each. Both Cardenases subsequently were sentenced to probation. Andrea Cardenas ended her re-election campaign.

The Ethics Commission settlement says Jesus Cardenas cooperated with investigators and agreed to take necessary and prudent precautions to ensure no future violations occur — and that if they do, he is on notice that future penalties will be higher.