Because the word "identified" comes with special significance. It's a positive identification from the police as a matter of fact, and it's an official position. It carries weight and is reportable without the risk of libel. A low-level lieutenant who heard a name and then told the media to curry favor is not identifying. He's providing a lead, which must be confirmed from another source.
Compare: We are positively identifying the suspect as John Doe, who is in custody.
With: Hey, we are looking at John Doe as the suspect.
One is identification, the other isn't. It's a legally-important word and distinction. Again, I worked in the field, and your shot at the end about my personal bias was uncalled for and marred your otherwise good parry.
A Law Enforcement Officer, provided the IDENTITY of the suspect. There fore IDENTIFIED by law enforcement is semantically and connotatively correct. An identification was made, and it was made by a member of law enforcement.
People on the other end of the TV do not ponder whether the identification was a legally-important one or not. They only know, via both of your examples, that a cop said that I guy named John Doe is a suspect.
The divide between intent and reality is in important concept to grasp, especially when you finally put your web application in the hands of soccer mom's and office administrators.
Compare: We are positively identifying the suspect as John Doe, who is in custody.
With: Hey, we are looking at John Doe as the suspect.
One is identification, the other isn't. It's a legally-important word and distinction. Again, I worked in the field, and your shot at the end about my personal bias was uncalled for and marred your otherwise good parry.