We already restrict the rights of non-participants in regard to Funeral processions.
Florida, for example;
(a) Regardless of any traffic control device or right-of-way provisions prescribed by state or local ordinance, pedestrians and operators of all vehicles, except as stated in paragraph (c), shall yield the right-of-way to any vehicle which is part of a funeral procession being led by a funeral escort vehicle or a funeral lead vehicle.
(b) When the funeral lead vehicle lawfully enters an intersection, either by reason of a traffic control device or at the direction of law enforcement personnel, the remaining vehicles in the funeral procession may follow through the intersection regardless of any traffic control devices or right-of-way provisions prescribed by state or local law.
Pennsylvania law requires “vehicles to stop for a funeral procession.”
North Carolina restricts the rights of drivers too:
(h) The operator of a vehicle proceeding in the same direction as a funeral procession shall not pass or attempt to pass the funeral procession, except that the operator of such a vehicle may pass a funeral procession when the highway has been marked for two or more lanes of moving traffic in the same direction of the funeral procession.
(i) An operator of a vehicle shall not knowingly drive between vehicles in a funeral procession by crossing their path unless directed to do so by a person authorized to direct traffic. When a funeral procession is proceeding through a steady or strobe-beam stoplight emitting a red light as permitted by subsection (c), an operator of a vehicle that is not in the funeral procession shall not enter the intersection knowing a funeral procession is in progress, even if facing a steady or strobe-beam stoplight emitting a green light, unless the operator can do so safely without crossing the path of the funeral procession.
As does Michigan:
You must yield for vehicles in a funeral procession
If we can have these traffic laws protecting the mourners, I can see no reason why we cannot prohibit protestors from shouting “Your child will burn in Hell!”, closer than 500 feet from a military funeral.
As another example, what’s the distance we enforce for pro-life protestors around an abortion clinic?
The funeral procession laws have attracted no criticism on the basis that they restrict free expression, though they certainly do, and though the arbortion clinic rules attract criticism, it is not from the ACLU. The ACLU, rather, raises “unintended consequences” that might affect abortion protestors as part of their criticism of laws proposing to restrict funeral protests. Ironic.
There is no reason that small limitations on the ability of homophobic protestors to attract press attention should cause any stir. The ability of military family members to address their bereavement privately is not a Constitutional issue.
If shouting “Fire!” in a crowded theater is a example of a limit to free speech, then so is shouting “He deserved to die!” at a soldier’s funeral.