WASHINGTON- The Justice Department said on Wednesday that it had met with state attorneys general to discuss concerns that social media platforms were "intentionally stifling the free exchange of ideas."In the statement, spokesman Devin O'Malley said that the department had monitored a hearing of a Senate Intelligence Committee on Wednesday, where Facebook Inc and Twitter Inc executives defended their companies before skeptical lawmakers. Many members of Congress fault social media platforms for failing to combat foreign efforts to influence U.S. politics."The attorney general has convened a meeting with a number of state attorneys general this month to discuss a growing concern that these companies may be hurting competition and intentionally stifling the free exchange of ideas on their platforms," O'Malley said in a statement.The companies have been criticized for what others see as an effort to exclude conservative voices.