There long has been significant debate over vaccines for children.

Proponents argue vaccines largely have eradicated many serious diseases. Opponents contend vaccines contain toxic substances that cause adverse reactions, and the decision should be left to parents rather than the government.

Now the debate is at the center of a lawsuit by the Association of American Physicians and Surgeons against Rep. Adam Schiff, D-Calif., who is known for running the Democrats' impeachment of President Trump

The AAPS announced on its website it joined with Katarina Verrelli in a federal suit alleging Schiff "has abused government power and infringed on their free-speech rights."

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"Who appointed Congressman Adam Schiff as Censor-in-Chief?" asked AAPS in a statement. "No one did, and he should not be misusing his position to censor speech on the internet."

Early last year, Schiff contacted Google, Facebook and Amazon and, using his authority as a member of Congress, told them to de-platform or "discredit" what he claimed was "inaccurate information" about vaccines.

A short time later, he boasted on his web page that the companies caved to his demands.

Karan Bhatia of Google told him: "We have put a lot of effort into curbing misinformation in our products – from better Search ranking algorithms, to improving our ability to surface authoritative content, to tougher policies against monetization of harmful or dangerous content. Under YouTube's Advertiser-Friendly Content Guidelines, we are and have been demonetizing anti-vaccination content under our longstanding harmful or dangerous advertising policy."

At Facebook, Kevin Martin said, "Our approach ... is to reduce the spread of inaccurate information about vaccines by reducing its distribution in News Feed, removing groups and pages that promote misinformation from recommendation surfaces, and providing authoritative information to people who might encounter it."

At the time, Schiff said the "scientific and medical communities are in overwhelming consensus that vaccines are both effective and safe."

"There is no evidence to suggest that vaccines cause life-threatening or disabling diseases, and the dissemination of unfounded and debunked theories about the dangers of vaccinations pose a great risk to public health," he said.

Schiff also took to the TV news circuit to promote his agenda:

AAPS pointed out that because of Schiff's campaign, Amazon "removed the popular videos Vaxxed and Shoot ’Em Up: the Truth About Vaccines from its platform for streaming videos, depriving members of the public of convenient access."

Twitter also added a "pro-government disclaimer placed above search results for an AAPS article on vaccine mandates: 'Know the Facts. To make sure you get the best information on vaccination, resources are available from the US Department of Health and Human Services.'"

"The internet is supposed to provide free access to information to people of different opinions," stated AAPS Executive Director Jane Orient, M.D. "AAPS is not 'anti-vaccine,' but rather supports informed consent, based on an understanding of the full range of medical, legal, and economic considerations relevant to vaccination and any other medical intervention, which inevitably involves risks as well as benefits."

AAPS said in its complaint against Schiff: "The First Amendment protects the rights of free speech and association. Included within the right of free speech is a right to receive information from willing speakers. Under the First Amendment, Americans have the right to hear all sides of every issue and to make their own judgments about those issues without government interference or limitations. Content-based restrictions on speech are presumptively unconstitutional, and courts analyze such restrictions under strict scrutiny."

A study published last year found 45% of American adults admit to doubting the safety of vaccines.

One of the doubters was Rep. Mark Green, R-Tenn., who said the federal government has "fraudulently managed" data regarding the problem.