tag.

Google and Face­book dis­played false in­for­ma­tion in the wake of the Las Ve­gas shoot­ing, again rais­ing con­cerns over peo­ple’s abil­ity to ma­nip­u­late the heav­ily traf­ficked plat­forms for so­cial me­dia and news.

The com­pa­nies said they promptly deleted the ma­te­r­ial, which had been pulled from web­sites by al­go­rithms search­ing for news about the mas­sacre. Shortly af­ter the shoot­ing, the “Top Sto­ries” sec­tion of Google’s search re­sults about the in­ci­dent in­cluded a chan­nel from the anony­mous mes­sag­ing board 4chan.org that iden­ti­fied the wrong per­son as the shooter. The thread has since been re-placed in the search re­sults by news ar­ti­cles.

Google said the 4chan search re­sult only sur­faced when peo­ple searched for the per­son wrongly iden­ti­fied as the shooter, a frac­tion of over­all queries. The mis­in­forma­tion ap­peared in gen­eral search re­sults—not its Google News prod­uct—an im­por­tant dis­tinc­tion because Google vets news sources that ap­pear in Google News re­sults, the com­pany said.

Google said it takes var­i­ous sig­nals into con­sid­er­a­tion when it comes up with its ranked search re­sults, in­cluding the trust­wor­thi­ness and time­li­ness of the source.

“Within hours, the 4chan story was al­go­rith­mi­cally re­placed by rel­e­vant re­sults,” a Google spokes­woman said in a state­ment. “This should not have ap­peared for any queries, and we’ll con­tinue to make al­go­rith­mic im­provements to pre­vent this from hap­pen­ing in the fu­ture.”

Face­book’s Trend­ing Top­ics sec­tion for the shoot­ing in­cludes a fea­tured ar­ti­cle and a mix of pub­lic posts gen­er­ated by an al­go­rithm. Some peo­ple who clicked through saw posts from Sput­nik, a Rus­sia-backed news out­let that has come un­der Jus­tice De­part­ment scru­tiny. The posts in­correctly re­ported the sus­pected shooter had ties to a ter­ror­ist group.

Af­ter ini­ti­at­ing a “Safety Check” for Las Ve­gas, which pro­vides in­for­ma­tion as a sit­u­a­tion un­folds, Face­book pop­u­lated the page’s top sto­ries with in­for­ma­tion from what ap­peared to be lit­tle-known sites, ac­cord­ing to screen­shots. These sto­ries have since been re­placed with news from more prom­inent out­lets such as NBC News. 

“Our Global Se­cu­rity Op­er­ations Cen­ter spot­ted these posts this morn­ing and we have re­moved them,” a Face­book spokesman said in a state­ment. “How­ever, their re­moval was de­layed, al­lowing them to be screen captured and cir­cu­lated on­line. We are work­ing to fix the is­sue that al­lowed this to hap­pen in the first place and deeply re­gret the con­fu­sion this caused.”

The dis­plays of mis­lead­ing Las Ve­gas in­for­ma­tion come as so­cial-me­dia com­pa­nies face in­creas­ing crit­i­cism over how they man­age plat­forms that have be­come a dom­i­nant way peo­ple find and con­sume news.