Police officers must be impartial and objective when performing their duties with the public. This does not prevent you from being a member of political parties in general. If you’re a member of or have previously been a member of a proscribed terrorist organisation or group, you won’t be eligible to apply.
The Home Office does not allow serving police officers to take an active role in politics. An active role in politics would include running as a candidate in an election but would not include basic membership of a non extreme political group or party as an example. You are not eligible for the programme if you plan to take an active role in politics whilst on the programme and serving as a police officer.