Not 13 but maybe 15 or 16.
Some people say "they are just children" but really who's fault is that? For at least the first couple centuries A.D. And earlier, people were married and supported themselves usually between 11-14. They handled all adult responsibilities, including sex. If they could do it then, why not now? The only reason 13 year olds are to immature is because of how we raise them. Mothers don't want their "babies" to grow up, father's want their daughters to stay "daddy's little girl" forever, and so they baby and coddle their children, some still holding their kids' hands WELL into their mid-twenties. This does them no favors. Also this isn't about adults taking advantage of minors, there are already plenty of laws regarding real rape and real sexual assault, and if your argument is "protect the children that I refuse to let grow up" then make laws for REAL rape and REAL sexual adult much stricter when the victim is a minor, but it should not be illegal for them to have sex. As things stand now even minor on minor sex is illegal, would you want your kid to go to jail as a minor for having sex with a minor boyfriend or girlfriend who may even be the same age?? Why should we call them criminals for doing what they are biological programmed to do? I think that right now 13 is too young (at the fault of the parents) but 15 or 16 is not. Most of them already have jobs in addition to school, they drive cars, they handle plenty of adult responsibility and they definitely know what sex is, what the risks are and there outcomes. So why not? Hell most of them are tried as adults if they break the law, why are they adults if they break the law but children if they want to have sex? And besides, most 15+teens are having sex anyway, why should we call them criminals for doing what their bodies are biologically programmed to do? If we were meant to have sex older than that, wouldn't puberty occur at a later age?? I say for now lower it to 15 or 16 everywhere then gradually change how we raise our kids, increase sex ed and actually teach them right from younger ages and watch as they prove to us again, as they had for centuries in the past, that they can, in fact, handle adult responsibilities, then at that point you could consider lowering it to 13.