One of the most memorable moments of last night’s Democratic primary debate was California Sen. Kamala Harris going after former Vice President Joe Biden for his opposition to school busing.

When Biden was a young senator in the 1970s, he opposed busing, which helped desegregate schools. Harris challenged his position on the issue, and said she had benefited from busing as a child growing up in California.

The exchange was memorable in real time. And according to Google search data, it also appears to have left a mark on Biden. Even as search traffic for Harris boomed, it saw a significant rise for “desegregation busing” among people who Googled Biden. In other words, Harris’s big moment had a lot of people looking more closely at Biden’s record on desegregation.

Here’s the exchange:

The moment clearly registered for the viewing audience. Google search volume for Kamala Harris skyrocketed in its aftermath. It dropped slightly for Biden.

But here’s what might be more notable: According to Google Trends data, a significant portion of people who have Googled Biden from that moment up through this morning also searched for “desegregation busing.”

Take a look at the chart below. Now, you might dismiss the line for “desegregation busing” because it was searched for less than Harris or Biden. But here’s another way to think of this: Since the debate ended, for every two searches for Joe Biden, there has been one search for “desegregation busing” — a search topic that virtually no one was searching in the hours prior. That is a lot of interest in an issue area tied to one candidate.

Most Americans know who Biden is, but Harris’s critique seems to have caused viewers to ask what exactly he stood for.

And the fact that he joined white conservatives to oppose a desegregation policy isn’t a good look — especially if some Democratic viewers are learning about it for the first time.

Biden’s answer in the debate was that he didn’t oppose busing outright; he just opposed the federal government’s role in busing — and he said he wanted it to be left up to local communities. But this “local control” defense echoed the rhetoric conservatives use to fight federal or statewide desegregation programs.

Busing was certainly unpopular with white families (and chances are it would still be quite unpopular today). It caused many white families to leave for the suburbs, where — thanks to the 1974 Supreme Court ruling in Milliken v. Bradley — they didn’t have to participate in inter-district desegregation plans.

But there’s overwhelming evidence showing that busing was one of the most effective desegregation policies since Brown v. Board integrated schools. And when busing was phased out in the 1980s and ’90s, schools actually started to re-segregate:

Biden had a poor performance on many fronts, but Thursday night’s debate appears to have many people digging into his record — and what they found likely made Biden look out of step with the other progressives onstage.