Why the police?

I too don't understand the police involvement (as others have said above)

Not paying for enough licences is a civil matter?

OK If I was selling pirate software on a car boot, or had a factory making pirate CD's then yes,. I'd expect the police to turn up eventually.

..... but if I installed my copy of windows at home on 2 of my computers (which would be a licence violation) then can I expect the police to be able to kick my front door in at 4am and raid my house?