Presidential candidate Julián Castro believes the media has been unfair to Senator Kamala Harris.

Castro, who served as the United States Secretary of Housing and Urban Development for the Obama administration, expressed the sentiments after Harris ended her presidential campaign on Tuesday. In a video tweeted by his national press secretary, Castro said the media "has basically trashed her campaign and focused on just one small part of it."

"The way the media treated Senator Harris in this campaign has been something else," Castro said, adding that she was unfairly held to a double standard. 

According to The Wall Street Journal, biased press coverage has been an ongoing discussion.

“One would be very naive not to believe that the owners of the media have an agenda as well,” presidential candidate Bernie Sanders told WSJ earlier this year. “It’s not just their attacks on me, that’s not what I’m talking about. It’s the issues that they allow for serious discussion.”

Sanders' campaign launched a newsletter in August to make sure the presidential candidate's voice is heard.

"We’ve said from the start that we will have to take on virtually the entire media establishment in this campaign and so far that has proven to be true," Sanders tweeted in August. "OK. Fine. We are ready."

According to commondreams.org, Sanders wrote an email to his supporters, saying "much of the coverage in this country portrays politics as entertainment and largely ignores the major crises facing our communities."

The 78-year-old added that "the corporate media is owned by a small number of large media conglomerates."

"As a result of massive mergers and takeovers, only a few large corporations like Verizon, AT&T, Comcast, Fox, Disney, Viacom, and CBS control the vast majority of what we see, hear and read," he said.  

FAIR, a publication that highlights media bias, recently conducted research on which topics were most discussed during the Ohio Debate in October. The study concluded that 30% of the questions given to the presidential candidates were about the economy, while 17% focused on non-policy issues.

Questions about abortion rights were only given to some candidates during the Ohio Debate, while issues concerning the climate, race, LGBTQ issues and immigration were completely ignored, FAIR reported.

In his Tuesday statement, Castro also said he commends Harris for the campaign she ran. 

"She’s one of the most qualified people running, and throughout this campaign, she’s run her campaign with class and with dignity,” the 45-year-old Democrat said.