questionable actions be i police officers. sometimes lead to major investigations. more now from tom llamas. >> reporter: because of this video, a florida highway patrol trooper is under investigation for tasering a 59-year-old man who had his hands up and also in florida -- >> stop! you're hurting me! >> a broward sheriff's deputy now on restricted duty when this cell phone video went viral showing him dragging an inmate deemed mentally incompetent through a courthouse hallway. the incident still being investigated. >> this was just so shocking, i figured that, you know, hopefully by pulling out the camera, this would stop, which, of course, it didn't. >> a growing number of citizens are using their cell phones to capture police officers on the job using questionable tactics. and their videos, sometimes leading to internal investigations. in south florida alone, in less than a month, three cases caught on camera, including this one.