Picketing

Per Merriam-Webster's Dictionary of Law, it entails picketing by a group, typically a labour or trade union, which inform the public about a cause of its concern.

Due to the numbers involved, and depending on behaviors, it may turn into an unlawful blockade such as a right of way obstruction, or aggravated trespass (denial of access).

Secondary picketing is of any external entity economically connected to the main business subject to the workers' action.

For example, at the Battle of Saltley Gate in 1972 in England, striking miners picketed a coke works in Birmingham and were later joined by thousands of workers from industries locally.

These flying pickets are particularly effective against multi-facility businesses that could otherwise pursue legal prior restraint and shift operations among facilities if the locations were known with certainty ahead of time.

In particular, religious groups such as the Westboro Baptist Church seek to picket local store fronts and events they consider sinful.

The global result is that the rules and outcomes are fact-sensitive (rest closely on the actions, form, subject-matter, duration and behaviors) and law-sensitive (divergently regulated or governed by case law).

It is possible, but rarely allowed in labor law globally, to have an informational picket in a public place of a business which has no simultaneous strike – i.e., a protest of workers outside of their shifts.

[12] In the US, this type of picketing, under Section 8(b)(7)(A) of the National Labor Relations Act, is typically illegal if representation is not relevant or is unquestionable.