Pictures of the US president have consistently been turning up in Google search results for the word “idiot” since at least the summer of 2018. Google’s CEO was summoned to the US Congress to explain to Democratic Representative Zoe Lofgren why this happens.

Google CEO Sundar Pichai explained at a congressional hearing how Google searches work and why pictures of Trump appear in search results for the word "idiot".

According to the executive, the results of any search are determined by hundreds of factors, such as popularity, freshness and relevance, which are based on data that Google collects from billions of webpages daily.

According to Google Trends, "idiot" is currently the number one most searched for term in the US.

Democratic congresswoman Zoe Lofgren posed the question about why "idiot" highlighted results that included pictures of the president.

"How would that happen? How does search work so that would occur?" she asked.

Mr Pichai replied that Google search results were based on billions of keyword ranked according to more than 200 factors, including relevance and popularity.

"So it's not some little man sitting behind the curtain figuring out what we're going to show the user?" responded Ms Lofgren.

Republican members of congress continued to grill Mr Pichai, with Steve Chabot asking why, when he searched for news about his party's health care bill, only negative news appeared.

Mr Pichai replied that equally negative news was highlighted when people used the search term "Google".