The police are actually doing quite a lot. One of the most sophisticated computer users in the United States, who posted his virus through a stolen account, and they arrested him within days. In the United States, the FBI, Customs, and most states actively investigate child pornography on the internet.
Most prosecutions involve people who trade or sell pornography.
Any person who sends any other person a pornographic picture of a child runs the risk that the recipient is a police agent. In many nations, police agencies have set up websites where they offer child pornography . They use these websites to accumulate information about frequent visitors. They may start the exchanges, or they may infiltrate an existing exchange, at which time they will do their utmost to convince participants to send them pornography. Those who do send pornography are investigated.