Aug. 31 (Bloomberg) -- Conrad Black and three other former Hollinger International Inc. executives indicted on fraud and racketeering charges are seeking permission to question lawyers and accountants who once did work for the newspaper publisher. Defense lawyers, in a filing last night, asked U.S. District Court Judge Amy St. Eve in Chicago to let them depose six attorneys at Toronto-based law firm Torys and three accountants at KPMG International. All of the potential witnesses are in Canada. ``Without an ability to procure testimony from these critical Torys and KPMG witnesses, defendants will be deprived of the ability to defend themselves at trial,'' lawyers led by Edward Genson and Mark Martin said in the filing. Black, 62, ran Hollinger International, now known as Sun- Times Media Group, for eight years as chairman and chief executive officer.