Nowadays, the media is a very convenient for information to get away quickly, we are exposed to all kinds of contents through these media, of which also includes detailed crimes aired, people believe their coverage should be strictly controlled, it appears like a good idea to me.
Firstly, the kids usually are not suppose to watch detailed crime scene as they may not have the mental capacity to accommodate the crime scenes shown in the media, a moderate level of exposure might be just fine, but if they encounter some photos, TV programmes or movies which are purely violent and criminal, they might try to mimic the behaviors shown in the media and even became one at their real life. In some cases, people with psychological conditions also might not be suitable to watch detailed crimes, and that could destabilize their fragile conditions.
Actually there are plenty of controlling methods already available at the market. The movie industry implemented a rule to classify the movies according their contents, such as explicit nudity or detailed crime descriptions, and the kids are not be allowed to view certain level of movies in the theaters. There also are signs at place in the theaters to remind people who have health conditions to watch movies with crime scenes with their own discretion. Some TV programmes operators also provide parental control with the channels of which will enable the parents to prevent their kids to view some specific programmes or channels.
To summarize, it's reasonable to have tight control over the exposure of detailed description of crime on the media in favor of our kids and people with conditions, and eventually benefit the common interest.