Stabler is shown visiting a family that is "sitting shiva" and ringing the doorbell to gain entrance to the home. "sitting shiva" is a custom that members of the Jewish faith follow when a member of the family dies. No family that is "sitting shiva" would lock their door and ringing the doorbell would never be necessary to gain entrance.
All the while Elliot is driving the shift handle is clearly visible.
Stabler pries a bullet fragment from the wall at the crime scene. No detective would ever do this, and not only disrupt chain of custody of the evidence, but potentially damage the evidence. That was a very sloppy piece of writing.