A man in Fukuoka, Japan who is on trial for murdering his wife’s niece during a confrontation with police has been spending his time in detention sending threatening letters to the judge.

The man, Tadashi Kawamura, 39, is due to receive a ruling on his case in the Fukuoka District Court on Thursday. During his trial he had shouted at witnesses, and he reportedly sent the letters because the case hadn’t proceeded as he expected it would.

Sources close to the case said about 100 letters were sent from Kawamura’s detention cell to the court and other places from December 2002. In statements he made to a judge in the letters, Kawamura said he would earn provisional release even if he received a life sentence and that if the ruling went against his will he would not forget it and there would be “trouble.”

During his trial, Kawamura has also been known to yell out suddenly during testimony of his family members, and has had two lawyers resign from his defense.