Speaking of bugging devices, if you go to Manchester have a look into the People's History Museum and you will see one that was placed in the CPGB's old offices in King Street, EC2.

From what I understand, it was found behind some old wood panelling but the associated text has no mention of this.

"This surveillance 'bug', discovered by builders in February 1975, was probably used by MI5 to spy on Communist activity. Former MI5 officer Peter Wright may have planted it, as in his book, 'Spycatcher', he describes concealing a 'bug' at Communist Party headquarters. The government did not admit responsibility for the device.

The Party issued this statement after its discovery;

"The Communist Party protests most strongly at the fact that this device was illegally installed in its premises. We are a legal political party not engaged in any conspiratorial activity and, like every other party we have the right to hold our committee meetings behind closed doors".

"not engaged in any conspiratorial activity"? Yeah, right.