It is imperative for Police Services throughout the UK to use Black ink ONLY when signing signatures for lawful documentation. I understand that there may be a need for other businesses to use purple/blue/red ink, however, within the Police and throughout the judicial process, any other colour than black ink will be rejected, which will lead to increase time an Officer or Investigators spend on obtaining signatures and investigating crime. Therefore, we require black ink, at the very least to be the default colour for signees.