Adam Schiff, Steve Garvey argue about Trump impeachment trial during California US Senate debate

Echoes of the 2020 impeachment trial against Donald Trump sparked a bitter exchange between California Senate candidates Rep. Adam Schiff and Steve Garvey at the U.S. Senate Candidate Forum on Tuesday.

The forum, hosted by ABC station KABC and the League of Women Voters of California and co-hosted by ABC stations KGO and KFSN, as well as media partner Univision Los Angeles, was also streamed on ABC News Live as part of a series of live-streamed U.S. Senate debates.

Asked by moderator and KABC Eyewitness News anchor Marc Brown about which presidential candidate they were each supporting, Schiff – who led the impeachment trial – said he was supporting Democratic nominee Kamala Harris and then turned his ire on Trump.

"Donald Trump, I think, was a disastrous president. I think he has threatened our democracy... Americans want someone who is good and decent and ethical and knows right from wrong, who's capable of telling the truth as the president of the United States. And the choice, to me is very clear, and it's Kamala Harris," Schiff said.

Garvey -- a former MLB player who has tried not to tie himself closely to Trump -- responded to the question by saying, "You've been trying to paint me for a year now into one corner or the other, and I've said, 'I'm running a Steve Garvey campaign. I make my decisions based on what I think is best for the people.'"

While running as a Republican, Garvey did not attend the Republican National Convention in July and Trump has not endorsed Garvey.

Garvey praised Trump, who he said he voted for three times, but added that Schiff is focused on Trump to the detriment of Californian voters. "I can't imagine how you could get up every morning and have one mission, and that's to go after Donald Trump. You were made a proxy by the higher-ups in your party… how can you think about one man every day and focus on that when you've got millions of people in California to take care of?"

"Mr. Garvey likes that particular attack because that's what Trump likes to say. It's his way of telling MAGA [Make America Great Again] viewers out there, 'Hey, I'm one of you.' That's not what Californians are looking for, Mr. Garvey," Schiff responded while defending his work as the impeachment manager.

Schiff then brought up being present during the Jan. 6, 2021 attack on the U.S. Capitol, adding, "The fact that you think that's perfectly OK, that you still want to support the guy who incited that violent attack -- that tells me that you would never take your oath of office as seriously as serious as I do."

Garvey took a moment to respond, prompting Schiff to mock, "I've left him speechless."

"I'm trying to think about all of the things that you've lost. You know, when you step up and you talk like you talk right now, it tells those hard-working people in California that you don't care about them. You care about something else," Garvey countered.

Garvey also criticized Schiff for being censured by the House of Representatives and from being later "banned" from the House Intelligence Committee as well. Both moves were spearheaded by Republicans and criticized by Schiff and Democrats as partisan politicking.

Both candidates are vying for the California U.S. Senate seat long held by the late Dianne Feinstein, who passed away in September 2023.

Schiff is a longtime member of the U.S. House of Representatives and was first elected to the House in 2000. Steve Garvey, a 10-time MLB All-Star, is a former Los Angeles Dodgers and San Diego Padres first baseman. More recently, he worked as a businessman and motivational speaker.

Analysts have not seen the race as too competitive, as opposed to the top-two primary, which was hotly contested.

In the deep blue state, Schiff currently has an over 30-point lead over Garvey in 538's current polling average for the Senate race, and his fundraising also dwarfs Garvey's by the tens of millions, according to an analysis by OpenSecrets.

But the race is one of 34 U.S. Senate seats up for election in 2024, as Democrats hope to hold the Senate and retake control of the House of Representatives, and as Republicans hope to flip the upper chamber.

Most of the debate focused on issues relevant to Californians, although some of them rank as issues that Americans nationally are focused on during the current election cycle.

On immigration and border security, both Schiff and Garvey support stronger border security, although they framed their views largely along their party lines.

Schiff called for both strong border measures and a humane policy, "We need to get control [of] the border. We need a strong border policy, which is going to require us, first and foremost, have more personnel along the border," he said, adding that better technology is needed to interdict people and narcotics. "But we also need a comprehensive immigration policy, that treats those that are trying to immigrate or migrate as human beings, that's consistent with our values," he said.

Garvey, afterward, voiced support for having a secure border and tied Schiff to what he framed as the current presidential administration's failure to do so.

"Let's face it, the times that I've been at the border when I've gone up and down, it's an existential crisis in this country that's been created by Joe Biden and with this man right here," Garvey said, saying that he would support reinforcing Border Patrol, reinstating the "Remain in Mexico" policy that required asylum seekers to not cross, and finishing the border wall.

On the economy and cost of living, Garvey said, "I think under Mr. Schiff's watch, over these last 25 years, you've seen this come to a situation now where we're much worse off than we were four years ago." He said he supports free markets and less restrictions on energy.

Schiff said he supports a low-income housing tax credit to incentivize building new housing units, as a way to alleviate the burden of the cost of housing, adding, "We also have to get local communities to approve housing much more quickly."

On trade, Garvey said later that he supports some tariffs on companies that threaten the success of American companies, but overall does not think tariffs are the answer to helping the economy, including less taxation on American companies "so that we can get all these products and services in this country without the need for importing from other countries."

Schiff said that he does not support "across the board tariffs" like the ones supported by Donald Trump, but that he supports "targeted tariffs when China is dumping steel or dumping other products or dumping technology to try to drive American businesses out of business."

Garvey also used the economy as a way to get in another dig at Schiff.

"As Mr. Schiff mentioned, about the economy and about getting the economy back -- well, I like to call that 'Schiff-flation', when he talks about the economy, and trying to get that to coincide, to kind of line with new innovations, like AI," Garvey said at another point in response to a question on artificial intelligence.

ABC News' Zohreen Shah, Olivia Rubin and Galen Druke contributed to this report.