'Why?' Motive remains a mystery but crime's impact is felt far and wide

It's one of the most-asked questions that I get," says the detective who helped bring to justice the two men who cut down the Sycamore Gap tree in the middle of a stormy September night two years ago.

- Mark Brown

"As soon as anybody knows I'm involved in the investigation, the first question is: 'Why?'"

Why would anyone cut down a tree that brought only joy and happiness to people? Did Daniel Graham and Adam Carruthers see it as a lark? Or a challenge? Was it a cry for help? A yell of anger?

Was it no more than an act of "drunken stupidity", as suggested by Carruthers' barrister, Andrew Gurney? Both men were sober, the prosecution argued.

DI Calum Meikle, of Northumbria police, genuinely does not know, he says, and thinks we might never know. "That is potentially the biggest frustration that people hold. Because if there was an obvious reason, if there was an obvious grudge, then people could understand it."

What the detective does believe is that Graham and Carruthers had no idea of the ramifications of what was described in court as a "moronic mission" to cut down the famous tree. "I don't think they fully understood the enormity of their actions." Graham and Carruthers were sentenced yesterday after being found guilty by a jury in May at one of the highest-profile criminal damage trials held in the UK. It is a measure of how seriously the state viewed the crime that one of the north's leading KCs, Richard Wright, led the prosecution, and a high court judge oversaw the case - Mrs Justice Lambert, who was, until 1 January, the presiding judge of the north-eastern circuit.

"It was just a tree," Carruthers told a jury, while also swearing blind he had nothing to do with its felling. The huge public and media reaction mystified him. "It was almost as if someone had been murdered," he said.

The sycamore tree in a dip on Hadrian's Wall in Northumberland was most likely planted in the late 19th century at the behest of the landowner John Clayton, Newcastle's town clerk who is recognised as "the man who saved Hadrian's Wall".