In the wake of the 2016 election, Instagram — known as the home of preening influencers, artfully arranged grain bowls and Icelandic vacation photos — somehow escaped much of the scrutiny of other social networks.
But two new reports suggest that may have been a mistake. The reports, conducted by independent groups and released by the Senate Intelligence Committee on Monday, concluded that Instagram — which is owned by Facebook — became a favored tool of Russian internet trolls after the 2016 election.
According to the reports, which were based on a trove of data provided by social media companies, Russia’s Internet Research Agency operated a vast network of accounts on Instagram that sought to infiltrate American identity groups, harden ideological divides and sow distrust in the American political system.
Much of the group’s activity was concentrated among several dozen large accounts, including one called @blackstagram_ and another called @american.veterans, both of which had more than 200,000 followers. Many of the group’s accounts targeted specific identity groups, including African-Americans, gun-rights supporters and anti-immigration activists.
In total, posts from Instagram accounts linked to the I.R.A. received nearly 185 million likes during the two-year period reviewed by the researchers, and about four million comments, according to the researchers. This activity accelerated in 2017, as Facebook’s stepped-up security measures after the election pushed the Russians to social media sites where they could troll more freely.
“On Instagram, I.R.A. activities did not cease after the 2016 election but became substantially more vigorous,” read one of the reports, which was written by Oxford University researchers along with Graphika, a company that maps social network activity.
The second report, written by researchers at the cybersecurity firm New Knowledge, concluded that Instagram was “perhaps the most effective platform for the Internet Research Agency” in terms of generating engagement.
“Our assessment is that Instagram is likely to be a key battleground on an ongoing basis,” the researchers wrote.
Facebook responded by saying in statement: “As we’ve said all along, Congress and the intelligence community are best placed to use the information we and others provide to determine the political motivations of actors like the Internet Research Agency. We continue to fully cooperate with officials investigating the I.R.A.’s activity on Facebook and Instagram around the 2016 election.”
A closer look at the Internet Research Agency’s posts reveals that the group used Instagram for several distinct purposes.
Pro-Trump, Anti-Clinton Activism
As on other social networks, the I.R.A. used Instagram posts before the 2016 election to generate support for Donald J. Trump and attack Hillary Clinton.
One post, made by an Instagram account called @feminism_tag, accused Ms. Clinton of insulting women who had accused her husband, Bill Clinton, of sexual misconduct. Another post targeted at African-American voters showed a manipulated image of Ms. Clinton with braided hair, and was captioned “when you need the black vote.”
In all, roughly 7 percent of the more than 100,000 Instagram posts included in the data set mentioned Ms. Clinton, while 11 percent mentioned Mr. Trump. There were no instances of pro-Clinton content on Instagram, according to the New Knowledge report.
Identity Group Cultivation
Many of the Russian posts focused on developing audiences among specific American identity groups, which could then be used to target them with content and advertising later on.
Several of the I.R.A.’s most popular Instagram accounts focused on African-American themes and interests. One image, posted to the @blackstagram_ account in June 2017, showed a series of women’s legs, with skin tones ranging from light to dark. The caption read, “All the tones are nude! Get over it!” It received more than 250,000 likes and more than 6,000 comments.
Another image, posted to an account called @army_of_jesus, encouraged users to “like if you believe,” and “keep scrolling if you don’t.” The account, which originally shared Kermit the Frog memes and jokes from “The Simpsons,” was later repurposed to target conservative Christians.
Several of the Instagram posts traced to Russia offered merchandise for sale. One post, shared by the @stay4police account, advertised T-shirts and hooded sweatshirts that read “I Support American Law Enforcement.” Other posts encouraged black Instagram users to support black-owned businesses with the hashtag #buyblack, and offered natural skin care products and other merchandise targeted at a black audience.
These merchandise sales most likely were not lucrative for the I.R.A. Instead, researchers suggested, selling merchandise had two other benefits: first, it allowed Russians to collect names, addresses and other personal information from users; second, it allowed them to identify strong supporters of a cause, who could then be targeted with advertisements.
Voter Fraud Rumors
In the days leading up to the 2016 election, some I.R.A.-linked Instagram accounts were used to seed doubts about the integrity of the election, and to accuse Democrats of trying to rig the vote in their favor. One image, shared by conservative-focused Instagram accounts, contained a false accusation of voter fraud in Pennsylvania. It was shared to Twitter and Facebook as well.
After Mr. Trump’s victory, the I.R.A.’s Instagram focus became more intense. In the six months following the election, the I.R.A. more than tripled its Instagram posting frequency, while its activity on Facebook increased by only 59 percent.
During this time, the Instagram accounts associated with Russia continued to post partisan content, much of which was recycled from other accounts.
The Russian Instagram accounts reached their peak of activity in May 2017, then experienced a sharp decline until October of that year, when they essentially disappeared from view.
That month, Facebook disclosed to Congress that it had identified and shut down more than 170 Russia-linked Instagram accounts, which had collectively posted about 120,000 times.
Kevin Roose is a columnist for Business and a writer at large for The New York Times Magazine. His column, “The Shift,” examines the intersection of technology, business and culture. @kevinroose • Facebook