San Mateo County Sheriff Christina Corpus's fight to keep her job entered a pivotal stage this week, as one of the central figures in the case, Victor Aenlle, took the stand for four hours of sworn testimony on Tuesday.

Corpus's former chief of staff has been accused of having an improper romantic relationship with the sheriff, but he has denied any such connection.

"Did you have a romantic relationship with Christina Corpus?" CBS News Bay Area asked Aenlle as he walked out of the courthouse.

"I did not," he firmly replied.

He characterized his support for Corpus as rooted in admiration for her leadership, not personal affection.

"She's a friend and I'm very proud of her because what she's endured, all the defamation and lies," Aenlle told CBS News Bay Area. "I hope the public wakes up and they see what's going on and they put an end to this because there's a lot at risk."

Legal analyst Steve Clark said Aenlle's testimony was critical to Corpus' case. 

"He is the undercurrent of the entire case, and if the Corpus team can dispel these rumors and say this was just an individual who wanted to be involved in government and see the county move forward, that will go a long way with the court," Clark said.

Aenlle portrayed himself as a devoted husband of 32 years, a father, and a longtime volunteer reserve deputy. He said his service was motivated by public duty, inspired by the murder of his brother.

But his testimony came in sharp contrast to former ally Valerie Barnes, who testified last week that she had witnessed foot rubs, affectionate texts, pet names, and even talk of marriage between the two. Barnes also claimed Aenlle gave Corpus diamond earrings, allegations both Aenlle and Corpus have denied.

Clark noted that even absent romance, the county may still argue that Aenlle's close relationship with the sheriff created an unfair advantage. "Even if it didn't rise to romantic, it could still be a conflict of interest," Clark said.

The county has pointed to Aenlle's lack of sworn law enforcement experience, noting that his rise through the volunteer reserve ranks set him apart from career deputies. Aenlle defended his role, insisting he represented civilian staff and carried legitimate authority in the office.

Corpus's attorney Tom Perez said the testimony underscored her efforts to change the department's culture. 

"Culture change is hard, and the reality is many of the senior leaders in the department want her to be removed," Perez said. "But I'm very optimistic moving forward."

Aenlle echoed that optimism: "I declare Sheriff Corpus will be victorious," he said.

Still, critics within the office described him as aggressive. Aenlle maintained he acted professionally and put the county first.

Clark added that the case ultimately hinges on whether the judge views the relationship, romantic or otherwise, as grounds for removal.

"There is no smoking gun here," he said. "Corpus' team is saying she was trying her best ... trying to convey a relationship that never happened."

The case also carries significant financial weight. Under Measure A, the county is covering the legal expenses of both sides, including its own outside counsel, Kelker, Van Nest & Peters, and Corpus' legal team at Murphy, Pearson, Bradley & Feeney. However, any further legal costs arising from separate litigation on behalf of Corpus must be paid personally.

County officials confirmed the proceedings remain on track to conclude on Friday.