parts of mexico, despite the fact that the levels of violence right now in mexico are as high or nearly as high as they have ever been. matt what about witnesses to that latest death? it looks like a busy street. is it the case that witnesses wouldn t fear speaking, wouldn t want to talk? reporter: yeah. there s a ton of reasons that these crimes are not solved. everything from local corruption to what you said, people are scared about talking. the impunity rates for murder in mexico are sky high. something about .3% of all murder cases where a prosecutor presents charges to a judge. that signals to criminals around this country, murder a politician, murder a candidate, you have an overwhelming chance of getting away with it. matt rivers, thank you so much, in mexico city. still ahead, a swarm of more than 600 earthquakes striking