McDonnell was forced into early retirement, historian Matthew Hughes speaks of his being dismissed from office, in October 1936, towards the end of the first wave of the Arab Revolt, and replaced by Harry Herbert Trusted in January 1937. McDonnell's retirement was induced by a series of clashes with Palestine's High Commissioner, Sir Arthur Wauchope, over the role of Palestine's judiciary in suppressing the "disturbances". This clash culminated in McDonnell's ruling in the "El Qasir v Attorney-General" (1936) 3 PLR 121 case. The decision pertained to house demolitions scheduled to take place in the old city of Jaffa. Although McDonnell ruled that the government had the authority to demolish the houses, he deemed the government's reliance on town planning justifications, rather than military necessity, an act of moral cowardice and accused it of "throwing dust" in the public's eyes.