Email marketers might find themselves in a quandary this Friday, when "Child Protection Registry" laws, intended to protect underage email users from adult material, take effect in Michigan and Utah, ClickZ reports. Marketers who send commercial email to inboxes in those states will have to monitor registries and ensure compliance, or face significant fines and even jail time. Anyone may place any email address in the registry, while schools and child-focused organizations may register their entire domains.

After 30 days, commercial emailers are prohibited from sending emails containing advertising for (including links to) products or services that is illegal for minors, such as alcohol, tobacco, gambling, prescription drugs, or adult-rated material.

Senders found to have violated Utah's law could face up to three years in jail and $30,000 in fines, along with civil penalties of $1,000 per message. Violators of Michigan's law would face similar fines and jail time, and be liable to civil penalties of $5,000 per message or $250,000 per day of violation.