In June of 2007, 24 year old Maurice V. Pulley Jr. was shot in the face over a parking dispute and survived. He received threats and bribes to not show up in court. He decided to testify, and was murdered during the trial.
This incident launched the Maurice V. Pulley Jr. Witness Protection Program, which still exist today. Resources for victims help, but as Maurice Pulley Senior will tell you, when you testify you pay a high price.