It was a perceived problem.
Freemasonry was blamed for everything in the 80s. There were books about it. It was in all the red-top newspapers. They were demonised as being some evil secret club where to be a member meant you subsumed yourself as if to some Eyes Wide Shut/Wicker Man type devil-worshipping cult, where they probably drank the blood of goats & burned small children in large wicker statues. Once you were high enough up the hierarchy, the world opened up for you like some all-pervading secret underground society who held all the purse strings & had the key to every door. Think what Dan Brown made of his Illuminati etc in the DaVinci Code, except these people lived just next door & you couldn't tell who was a member, unless you knew the funny handshake.
The trouble is, the freemasons could never respond; it's against their 'charter' or whatever they have, so the journos speculated to their heart's content.
You only need to add to this that both the police & the 'crims' must now, of course, all be in the very same lodge [and probably play golf together at the weekend] & you have a lot of room for the wildest speculation, with no fear of anyone ever actually disabusing you.
My father in law was at one time [not in the UK, though he is British] the second highest ranking member in his country's entire Freemasons society. Literally only one person senior to him.
He once explained this entire misconception to me quite concisely as a 'load of old bollocks', but couldn't tell me any details either, beyond yes, they wear funny aprons & odd medallions and sashes - I've seen his & ordinary members of the public can visit Masonic halls to see some on display [I filmed a couple of nights in the big one in London for Assassin's Creed; they're really not hidden away]. Yes, they have really, really long ritual speeches for ceremonies which must be done from memory. He says he did well in the organisation mainly because he's good at remembering speeches.
No, goats & small children are quite safe, though they're not actually allowed in the building at all.
I think as a story element, to go with the press frenzy about it all at the time, you may as well 'blame the masons'. Everybody did.