It was said that this was because Ometsuke officers and Metsuke officers, who were originally people outside the trial work, were prohibited from reading criminal-related laws and regulations including Kujigata-osadamegaki (the law of Edo bakufu).
これは公事方御定書をはじめとする江戸幕府の刑事法規を本来裁判業務の部外者であった大目付・目付が見ることが禁じられていたことによるという。