SUMMONS FOUGHT BY CUNNINGHAM IN NADJARI CASE
NYS Dem Chmn Patrick J Cunningham seeks to quash special state grand jury subpoena asking him to testify about possible purchases of judgeships in Bronx on grounds that Special NYS Prosecutor Maurice H Nadjari lost all power and auth to act as deputy atty gen when Gov Carey dismissed him Dec 23, ct papers; apparently asks Sup Ct Justice John M Murtagh to rule on Nadjari's status; also holds Nadjari has gone beyond scope of his mandate; Atty Gen Lefkowitz rejects Gov Carey's request to name Michael F Armstrong as interim special prosecutor until Nadjari can be replaced by Dist Atty Robert M Morgenthau; agrees to Carey's bid to name special deputy atty gen to probe charges that Carey ousted Nadjari because of pol pressure; says his decision to retain Nadjari for 6 more mos was made in public interest; says probe must not interfere with pending investigations and grand jury proceedings; notes Carey has agreed on point; concedes inquiry will have problems; Carey hails Lefkowitz's acceptance of probe; Nadjari, in reversal of his private views, lauds idea of probe; trusts nothing will be done to impair his investigation; pledges cooperation; Lefkowitz illus (M)