Great and eyecatching poster. I can understand that many countries have a history where the police were only servants of the State/political party rather than the law or the citizenry but it isn't universal.
We in Ireland had Europe's first unarmed police force the Gardaí Siochana (Peace Guards), this was to distinguish them from their predecessors the Royal Irish Constabulary who were definitely political animals and who would call on and command the army to help them in their work.
During the 1913 Lockout they were known for attacking & killing strikers and this resulted in the founding of the Irish Citizens Army so that workers could protect themselves from the police and the factory owners hired thugs, they also took part in our national revolution(just put some old photo's of these guys up)
Most small villages and towns here have a Gardaí and they are definitely looked upon as being servants of the public rather than someone to fear.
I especially liked your "We are not the enemy" poster, it was very original.