R. David b. Samuel Friedmann (also called "Dovidel" Karliner; 1828–1917), Lithuanian rabbi and posek. R. Friedmann was born in Biala and lived for a time in Brest-Litovsk after 1836. On the advice of R. Leib Katzenellenbogen he moved to Kamenets-Litovsk where he studied under the supervision of his older brother R. Joseph until 1841. In that year he made the acquaintance of the philanthropist Shemariah Luria of Mohilev, who entrusted to him the education of his brother-in-law Zalman Rivlin of Shklov. R. Friedmann later married Luria's daughter. From 1846 to 1866 he devoted himself to concentrated study in the house of his father-in-law, where he compiled his Piskei Halakhot. After the death of his father-in-law in 1866 he accepted the rabbinate of Karlin near Pinsk (in 1868) where he remained until his death.

R. Friedmann's renown rests upon his Piskei Halakhot (pt. 1, 1898; pt. 2, 1901), an exposition and summary of matrimonial law, with a commentary entitled Yad David, an appendix entitled She'ilat David containing responsa on the laws of mikva'ot ("ritual baths"). The text of the Piskei Halakhot follows that of Maimonides. In his comprehensive exposition, R. Friedmann endeavors to establish clear-cut decisions. His work is distinguished by the fact that he relies to an overwhelming extent on the Babylonian and Jerusalem Talmuds and on the rishonim, disregarding the aharonim. He eschewed casuistry and tried to penetrate to the essence of the halakhah by a logical approach. Among the rabbis who turned to him with their problems were R. Menahem Mendel Schneersohn, the head of the Lubavich (Habad) dynasty, and R. David Luria. When religious extremists in Jerusalem excommunicated the bet midrash of his brother-in-law, R. Jehiel Michael Pines, because he supported the establishment in Jerusalem of an orphanage "where they would also learn a foreign language," R. Friedmann attacked them in his Emek Berakhah (1881). It consists of four essays in which he discusses the question of a ban and the regulations and conditions under which it should be imposed, emphasizing that a handful of rabbis of Jerusalem had no right to impose such a ban. R. Pines wrote a long introduction to the book. Even though he tended to view with favor secular knowledge and the study of languages, R. Friedmann was opposed to compromise with regard to Torah education and the character of the traditional heder and in 1913 vehemently opposed the plan of the society Mefizei Haskalah be-Rusyah ("Disseminators of Secular Education in Russia") to change the accepted curriculum of the heder.