"The burden of evidence required on each side is "essentially" the same"

The BBC report Home Secretary (and the BBC's new favourite Labour minister) Alan Johnson as saying re the upcoming extradition of Gary McKinnon that:

"Home Secretary Alan Johnson told them the 2003 treaty had simplified extradition procedures while safeguarding defendants' rights.

The burden of evidence required on each side is "essentially" the same, he added."

Really? I suppose this one boils down to Alan Johnson's definition of "essentially", somehow I don't think it's the same as mine... Would Alan Johnson care to comment?