Moreover, in two judgments from 1969 and 2008 (95), the Supreme Court of Japan has stipulated limitations with respect to non-compulsory measures that interfere with the right to privacy (96). In particular, the court considered that such measures must be "reasonable" and stay within "generally allowable limits", that is to say they must be necessary for the investigation of a suspect (collection of evidence) and carried out "by appropriate methods for achieving the purpose of [the] investigation" (97). The judgments show that this entails a proportionality test, taking into account all the circumstances of the case (e.g. the level of interference with the right to privacy, including the expectation of privacy, the seriousness of the crime, the likelihood to obtain useful evidence, the importance of that evidence, possible alternative means of investigation, etc.) (98).