Could you please check and improve my sentences?

Alan Shatreka is a 73 year old English writer. He recently wrote a book on Singapore court activities where he strongly criticized their practices. He highlighted the fact that the court issues death sentences even for small crimes. Subsequently, the Singapore government filed a case against him for allegedly libeling the judiciary and the judge sentenced him to prison. However, he appealed against the case in the high court. In turn, the high court judges sentenced him to an eight week sentence, together with a ten million dollar (US) fine for allegedly insulting the judiciary. The judges extended his eight week imprisonment to ten weeks when he told them that he didn’t have enough money to pay the fine.