As the saying goes: A few bad apples spoil the bunch. There are numerous examples of police brutality in recent American history. The actions of these few do not represent law enforcement as a whole. However, due to the increased presence of both social and print media, the way law enforcement is perceived has been greatly altered. Now more than ever, the police are viewed as the enemy, and as a result too many officers have lost their lives.
There appears to be a backlash against the police due to perceived brutality practices. There have been documented cases of people specifically targeting police officers due to news coverage of alleged brutality. While police officers are not perfect and there are rotten apples, this shold be judged in a court of law.
In modern society, people know that police have no power. Police are highly scrutinized with 20-20 hindsight for decisions that they have to make in seconds. Because society knows that law enforcement can't fight back, the number of police deaths have increased because people have to boundaries with law enforcement. The number of demonstrations around the country against police illustrate this.
Actually the overall number of police deaths have gone down since 2011. In 2011 the number of police officer deaths was at 171 and has decreased since then. Now the number of officers shot and killed has gone up from 2013 to 2014 from 33 to 48 but, their is no way to know if this is due to backlash from police brutality or not as of this time.
While police brutality has become a bigger issue with an increasing number of incidents being filmed and shared, police have long had a tenuous relationship with some communities and are seen as outside invaders in some. Prior to the rash of police brutality incidents and subsequent protests, police were just as likely to face violence when trying to apprehend an individual or group who knew they were going to prison for a long time already.