Google co-founder Larry Page and Google CEO Sundar Pichai declined the offer to participate before Congress at the Senate Intelligence Committee to follow up on the meeting that took place in November regarding the Russian election interference. The discussion centered on how big tech companies are preparing for midterm elections.

The third hearing  being streamed included questions such as whether Facebook has a moral and legal obligation to take down accounts that insight violence, who sets the standards to determine the definition of coordinated manipulation, and whether its platforms discern between U.S. and non-U.S. citizens.

“We don’t always know where an account is coming from,” said Twitter CEO Jack Dorsey during the hearing. He also made note that the company has been building machine-learning technology to identify behavioral patterns to determine fake profiles.

One senator expressed her “outrage” that Google did not appear at the table. 

While Dorsey and Facebook COO Sheryl Sandberg attended the meeting to testify, Google followed up by sending remarks in a written letter. On Tuesday Kent Walker, Google’s senior vice president of global affairs and chief legal officer, published the written remarks it plans to deliver.

“We believe that we have a responsibility to prevent the misuse of our platforms and we take that very seriously,” Walker wrote in the blog post. “Our efforts in this area started many years before the 2016 election.”

Walker wrote that the company continually works to detect and minimize opportunities for manipulation and abuse, constantly tackling new threats.

Those steps include an ID verification program for anyone buying ad space from Google to promote the U.S. federal election, in-ad disclosures attached to election ads across its products, a transparency report specific to political ads on Google and a searchable ad library that allows anyone to view political ads for candidates in the U.S.