This isn't just a smoking gun

it's a siege cannon with the barrel still hot:

From the CRU code file osborn-tree6/briffa_sep98_d.pro , used to prepare a graph purported to be of Northern Hemisphere temperatures and reconstructions.

;
; Apply a VERY ARTIFICAL correction for decline!!
;
yrloc=[1400,findgen(19)*5.+1904]
valadj=[0.,0.,0.,0.,0.,-0.1,-0.25,-0.3,0.,- 0.1,0.3,0.8,1.2,1.7,2.5,2.6,2.6,$
2.6,2.6,2.6]*0.75 ; fudge factor
if n_elements(yrloc) ne n_elements(valadj) then message,’Oooops!’
;
yearlyadj=interpol(valadj,yrloc,timey)

This, people, is blatant data-cooking, with no pretense otherwise. It flattens a period of warm temperatures in the 1940s -- see those negative coefficients? Then, later on, it applies a positive multiplier so you get a nice dramatic hockey stick at the end of the century.

Via Donald Sensing