Motion Picture Assn. of America president and chief executive Jack Valenti spoke out Thursday against potential congressional restrictions on violence on television, and pledged that member studios will vigorously police what is put on the small screen.“Both the broadcasting industry and the creative community have pledged to try to reduce excessive violence on the screen,” said Valenti, speaking before the Town Hall of California. “We will do this because we ought to.” Citing a National Research Council study titled “Losing Generations: Adolescents in High Risk Settings,” Valenti said the issue of violence among youths in America runs deeper than television. He suggested a national focus on such issues as gun control, poverty, education and parental influence. The speech, delivered at the JW Marriot Hotel in Century City, comes just weeks after the Big Three networks and Fox Broadcasting Co. unveiled a plan to place parental advisories on programs containing violence (Daily Variety, July 1 ). But the move by the networks to install advisories has not silenced debate over TV violence. Rep. Ed Markey (D-Mass.) said Thursday he will introduce legislation on Capitol Hill requiring TV manufacturers to install a microchip in new sets that would allow parents to block out shows deemed violent (see separate story). Valenti said the MPAA will fight “a chip that with one press of a button could exile a whole day’s programming or a whole week’s programming.” He disputed research suggesting that violence in society is fostered by violence on television. He said low homicide rates in Canada, Japan and the United Kingdom, which broadcast American television product, throws into question whether domestic TV shows engender violence. The MPAA exec said that unless there is gun control in the United States, the issue of television violence will be batted around “like a shuttlecock in a badminton game.” In the course of the address, Valenti referred to such literary sources as Alexis de Tocqueville, Goethe, poet Scott Holland, Queen Elizabeth I, an old Southern prayer and William Faulkner’s Nobel Prize acceptance speech.