It may sound hard to believe, but under Iowa law there are times when an adult can be held accountable for the actions of other adults over whom they have no control. Generally, under most acceptable theories of criminal punishment, a person should not be punished for people or things over which they have no control, but Iowa statute 124.407 begs to differ.
This statute makes it unlawful for any person to promote, sponsor or assist in a gathering of people with the knowledge that a controlled substance will be distributed, used or possessed at such gathering. Read literally, this means that any person who possibly knows that a person arriving at a party or gathering of friends who possesses marijuana or any other illegal drug could be held liable and found guilty of a misdemeanor or even felony. This law puts a tremendous amount of liability on a person hosting people or even just inviting a friend over for dinner. If that friend lights up a joint, even without the host's permission, that person is potentially culpable under this law.
Even more interesting is that this law allows law enforcement to get an injunction to stop a gathering if they believe that the host hasn't taken reasonable means to prevent others from possessing or using drugs at the gathering. Given this drastic law, it's quite amazing that concert promoters in Iowa somehow manage to stay in business.
When it comes to drug offenses in Iowa, the laws cast a wide net in hopes of deterring people from using, possessing or distributing controlled substances. Unfortunately, this creates a law enforcement culture where they would rather arrest first and ask questions later. People who find themselves facing criminal charges need to present their defense in order to avoid prosecution and conviction. Anyone facing drug charges should discuss their situation with an experienced Iowa criminal defense attorney.
Source: Iowa Code, "124.407," accessed Dec. 1, 2014