Senator Ben Sasse called Monday for the Attorney General to investigate the website Pornhub. The senator said the site had promoted videos showing the sexual assault and rape of a victim of human trafficking.

"The foremost duty of the Department of Justice is to ensure the safety of the American people, especially the most vulnerable among us," Sen. Sasse (R-Neb.) wrote in his letter to Attorney General Barr on March 9.

In the letter the senator asked for a federal investigation into the online pornography platform, and its owner MindGeek, citing the promotion of videos that exploited a trafficking victim.

In a statement on the letter released Tuesday, Sasse cited "several notable incidents over the past year" where Pornhub promoted content online "showing women and girls that were victims of trafficking being raped and exploited."

Sasse also highlighted cases in which women were coerced into performing sex acts for a video that was uploaded to the site without their consent

"Pornhub must not escape scrutiny. I therefore request that the Department open an investigation into Pornhub and its parent entity MindGeek Holding SARL for their involvement in this disturbing pipeline of exploiting children and other victims and survivors of sex trafficking," Sasse wrote in his letter to the Justice Department.

Pornhub has come under widespread scrutiny in recent months, after videos showing the sexual abuse and rape of a 15 year-old girl appeared on the platform in 2019.

The girl in the videos had been missing for a year and reportedly was raped and forced to have an abortion. Her mother saw her on the website-a discovery that led to the arrest of the girl's captor Christopher Johnson.

"These publicized cases clearly represent just the tip of the iceberg of women and children being exploited in videos on Pornhub," Sasse wrote Monday.

As of Tuesday morning, more than 425,000 people have signed an online petition at change.org calling for PornHub to be shut down. The petition also calls for its executives to be held accountable for alleged complicity in human trafficking.

In November, the payment vendor PayPal abruptly cut payment services for Pornhub.

Pornhub has touted 39 billion internet searches in 2019, nearly seven million video uploads, and more than 80,000 visits per minute, according to Sasse's letter.

Sasse's letter comes after four members of Congress in December petitioned the Department of Justice (DOJ) to enforce existing obscenity laws and prosecute pornographers.

Reps. Jim Banks (R-Ind.), Vicky Hartzler (R-Mo.), Mark Meadows (R-N.C.), and Brian Babin (R-Tex.) wrote Attorney General William Barr, asking him to resurrect the Obscenity Prosecution Task Force in the DOJ's Criminal Justice Division. The task force was charged with investigating and prosecuting makers of hard-core pornography.

Fifteen state legislatures have already declared pornography to be a "public health crisis," and President Donald Trump signed the Children's Internet Safety Presidential Pledge while a candidate for the presidency in 2016, commiting himself to enforce obscenity and anti-child pornography laws as president.

Pope Francis, in a November meeting with technology executives, brought up the problem of children being exposed to pornography at an early age. "This is in no way acceptable," he said, urging the executives to "assume their responsibility" and protect children from pornography.

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