One of the more persistent myths of our time.

From Wikipedia:

"The penalty for treason was changed from death to a maximum of imprisonment for life in 1998 under the Crime And Disorder Act. Before 1998, the death penalty was mandatory, subject to the royal prerogative of mercy. Since the abolition of the death penalty for murder in 1965 an execution for treason was unlikely to be carried out."

Not sure what my point is.