if you torture the data long enough, it will confess to anything

Etymology
This phrase was coined by economist. A closely related sentence had been published in 's book L'Opinion publique (The public opinion, éd. Presses universitaires de France, coll. « Que sais-je ? », 1961, p. 100):

The figures are innocent people who, under solicitation, under torture, very quickly confess what is asked of them, even if it means retracting later. (Les chiffres sont des innocents qui, sous la sollicitation, sous la torture, avouent très vite ce qu'on leur demande, quitte à se rétracter plus tard.)

Proverb

 * 1) Statistics can be manipulated to support any conclusion.