I am just as sure that neither he, nor anyone else, can provide proof of a successful prosecution against anyone which involves only that of a person who fails to declare they live abroad. We are not talking false claims for any "benefits" like winter fuel or anything else, just about anyone having a UK address while living overseas and claiming the basic UK pension.
Answers, with proof, on the back of a postage stamp please!
Please do not bother with a "friend" story. A newspaper cutting etc will do nicely!!