Arizona's law prohibits people from filming police officers within short distances. Those who do not comply could face fines or even jail.
Critics refer to the law as a threat to freedom of speech and the right for a free press.
Bystanders often film police officers and occasionally, it has led to misconduct by officers.
On September 24, the law will be in effect. It will be illegal to film officers of the state from a distance of less than 8 feet (2.4m).
If you ignore a warning and continue to film, you could be charged with a misdemeanour and spend up to 30 days in prison.
However, the law makes exceptions for those who interact with police or within an enclosed area on private property.
John Kavanagh, a state representative who sponsored the bill, said it was necessary because "groups hostile towards the police" can sometimes "get dangerously near to potentially violent encounters".
USA Today's March issue stated that "Getting too close to police officers during stressful situations can lead to tragedy." "Police officers don't know if the person approaching them is innocent or a accomplice of the suspect they are arresting for assaulting them."
Opponents of the law, however, say it attempts to discourage people from exercising their rights to film on public property, violating their constitutionally-protected First Amendment rights to free speech.
The National Press Photographers Association, an industry group including still and TV news photographers, filed opposition to the law in February. They argued that the law "violates the clearly established right of police officers to photograph and record their official duties in public places." ".
The debate about police brutality and misconduct, especially against African Americans, has been dominated by footage from bystanders.
A 17-year old bystander took video of George Floyd's murder at the hands Minneapolis police officer Derek Chauvin. Later, it was a crucial part of the case against Chauvin.
Chauvin was sentenced this week to 20 years imprisonment for violating Mr Floyd’s civil rights. He is currently serving a 22 year sentence in the state for murder.
