Now, the government is having a conflict (http://en.wikipedia.org/wiki/2013_corruption_scandal_in_Turk...) with the Gulen Movement (http://en.wikipedia.org/wiki/G%C3%BClen_movement), which they used to be buddy-buddy with, and now no one seems to trust the police anymore, not even the government themselves. The government has been sacking police chiefs and reassigning commanders all over the country, in an attempt to break up any Gulen supporters, and to seize power over the police again.
Looking at the Peelian principles, they've failed 1 many times before by taping over helmet identification numbers (http://www.ataturk.org/wp-content/uploads/2013/07/same-story...) and they've also failed 3 many times by engaging in cronyist tactics to avoid prosecution and accountability, even with evidence.
Looking over the principles of policing, they've failed #2 since there has been widespread condemnation of police brutality, and the force is still there. They failed #4 when riot police attacked a camp of sleeping peaceful protesters at 4am with tear gas and batons. They failed #5, since the police chiefs are appointed by the current political party, and thus are not impartial. #6 is the same as #4. #8 goes along with #5, and also when police have been seen attacking people of specific political leanings, or refusing to carry out orders to arrest people of their own political leanings.
My two main observations from all this are: First, like the judiciary, I believe the police force should also be completely isolated from the executive branch in terms of receiving orders and in terms of placement, hiring and firing of personnel. This prevents them becoming cronies of the current political power, and follows separation of powers.
Second, I believe that the police should be paid at least average salary (way above poverty level) and be required to have at least average education (not merely primary school education). Otherwise, it becomes difficult to have the sorts of people who can meditate on concepts like cronyism, whistleblowing, consent of the governed, blindly following orders, etc. It becomes easier to have the sorts of people who are poor and likely to accept bribes, politically fired up and filled with hatred, power tripping.