Most of the day was spent in the car, so I felt a good early morning run would prepare me well. I went to prison today to meet a former Sergeant in the Royal Marines, better known as Marine A. His real name is Alexander Blackman and he is married to the charming Claire and has been for five years. I have always felt uneasy about Mr Blackman's conviction and that feeling led me to visit him in prison today. I made contact through his wife and after she'd approved my suggestion I arranged to visit. All prisons are pretty gloomy and this one was no different. Having gone through all the preliminaries, I was ushered into a interview booth with four chairs and a table. Moments later Mr Blackman entered. He's a big man and looks every inch the part of a Royal Marine Sergeant. He's been through four tours of Iraq and two in Afghanistan, all at our command. His record was exemplary until that fateful day in Helmand Province in 2011. He put a bullet into an injured Taliban insurgent, which was filmed from a helmet-mounted camera. After a three week trial, Mr Blackman was convicted of murder and jailed for life, with a minimum term of 10 years, later reduced to eight on appeal. His sentence was controversial and many thought he'd been made a scapegoat. I listened for 90 minutes to Mr Blackman and his account raised more questions than answers. He came across as a very level-headed man, who I would certainly have wanted in my platoon when I was serving. He certainly did not come across as a cold-blooded killer. There are various questions to be asked and that is in process and my unease was not lessened by my visit. Mr Blackman has seven more years to serve, a very high price to pay for putting his life on the line on so many occasions for us.