 Thus, the test results obtained by the commission appeared to confirm that the works were forgeries created by van Meegeren, but their authenticity continued to be debated by some of the experts until 1967 and 1977, when new investigative techniques were used to analyze the paintings (see below).On 12 November 1947, the Fourth Chamber of the Amsterdam Regional Court found Han van Meegeren guilty of forgery and fraud, and sentenced him to a minimal one year in prison.While waiting to be moved to prison, van Meegeren returned to his house at 321 Keizersgracht, where his health continued to decline.