Biography
Phil Bart was a former general manager of the Daily Worker who was convicted of contempt of Congress after refusing to answer questions from the House Un-American Activities Committee. The court imposed three months in prison and a $500 fine. The Supreme Court reversed the conviction and ordered his acquittal on May 23, 1955.
The official House Clerk returns for the November 4, 1930 congressional election list Phil Bart as a candidate for Michigans13th Congressional District, printed Philip Bart with the Workers designation. This corroborates electoral activity rather than a fresh arrest or custody endpoint. Source: https://clerk.house.gov/member_info/electionInfo/1930election.pdf#page=11
The Detroit report names Philip Bart, Morris Fleishman and Alfred E. Goetz as arrested when police broke up an election meeting. It says two detectives beat them unconscious, they were held incommunicado two days, and the court freed them without charges. The two-day interval is source-reported, with no exact endpoints; it is separate from later arrests.
The July12 Detroit report describes renewed questioning during his recent election-meeting detention about anti-military-training stickers posted July4. Federal officers claimed a League instruction letter but did not produce it when challenged. Two Party members arrested with him were likewise questioned. This amplifies the already recorded Detroit arrest, not a separate new detention.