
Picketing is a form ofprotest in which people (called pickets or picketers)[1] congregate outside aplace of work or location where an event is taking place. Often, this is done in an attempt to dissuade others from going in ("crossing the picket line"), but it can also be done to draw public attention to a cause. Picketers normally endeavor to benon-violent. It can have a number of aims but is generally to put pressure on the party targeted to meet particular demands or cease operations. This pressure is achieved by harming the business through loss of customers and negative publicity, or by discouraging or preventing workers or customers from entering the site and thereby preventing the business from operating normally.
Picketing is a common tactic used bytrade unions duringstrikes, who will try to prevent dissident members of the union, members of other unions and non-unionised workers from working. Those who cross the picket line and work despite the strike are known pejoratively asscabs.

Informational picketing is the legal name given to awareness-raising picketing. Per Merriam-Webster'sDictionary of Law, it entails picketing by a group, typically a labour or trade union, which inform the public about a cause of its concern.[2] In almost all cases this is a disliked policy or practice of the business or organisation. It is a popular picketing technique for nurses to use outside of healthcare facilities. For example, on April 5, 2006,nurses of the UMass Memorial Medical Center (UMMHC) took part in two separate such events to protect the quality of their nursing program.[3] Informational picketing was used to gain public support and promote further bargaining with management.[3] It may also be a spur or auxiliary to a petition to government to seek regulatory intervention, reliefs, dispensations or funds.
Amass picket is an attempt to bring as many people as possible to a picket line to demonstrate support for the cause. It is primarily used when only one workplace is being picketed or for a symbolically or practically important workplace. Due to the numbers involved, and depending on behaviors, it may turn into an unlawfulblockade 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. Thus it includes against suppliers on which the picketed business relies, retailers who sell its products, physical premises with shared management or majority shareholders (sister/allied premises) and homes of any of the latter persons. For example, at theBattle of Saltley Gate in 1972 in England, striking miners picketed acoke works inBirmingham and were later joined by thousands of workers from industries locally. In most jurisdictions, secondary pickets lack all or many of the civil law protections given to primary pickets.
Secondary picketing has been illegal (in the sense that, unlike lawful picketing, it may give rise to a cause of action intort) in theUnited Kingdom since the coming into force of section 17 of theEmployment Act 1980,[4][5] a law tabled and passed by theConservative government ofMargaret Thatcher.Labour sought repeal of this via the party's1987 manifesto; the party called for a debate on such issues in the next (1992) manifesto; and dropped this position underTony Blair and later leaders' manifestos from1997 onwards.[6]
Another tactic is to organise highly mobile pickets, who can turn up at any of a business's locations quickly. Theseflying pickets are particularly effective against multi-facility businesses that could otherwise pursue legalprior restraint and shift operations among facilities if the locations were known with certainty ahead of time. The first highly strategic use of such may have been the example of the1969 miners' strike in Britain.[7] Flying pickets are usually not legal in the United Kingdom; workers must only picket at their workplace.[8]
Picketing can interweave withboycotting campaigns bypressure groups across the political and moral spectrum. In particular, religious groups such as theWestboro Baptist Church seek to picket local store fronts and events they consider sinful. Non-employee protesters are third parties to the business so counter-actions may lie in the courts (or out-of-court remedies) for disruption of trade, unlawful protest, defamation, and certain types of illegal advertising, trespass and nuisance, against which freedom of expression, of religion and/or a public interest defense vie. Different jurisdictions weigh these two competing sets of rights differently. 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).

Disruptive picketing covers a wide variety of pickets:
Obstructive picketing may be contrasted withnon-obstructive picketing, in which the impact on the business or organization is likely to be limited to the presence nearby of a group of people close in number to the number of strikers, who have an informational picketing line, assembly or rally. 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. In some sectors, the immediate financial impact of a non-obstructive picket could be negligible, and the longer-term impacts could include ahuman resources policy or public-facing policy enhancement and a consumer relations uplift.[clarification needed]

Picketing, as long as it does not cause obstruction to a highway or intimidation, is legal in many countries and in line withfreedom of assembly laws, but many countries have restrictions on the use of picketing.
Legally defined, recognitional picketing is a method of picketing that applies economic pressure to an employer with the specific goal to force the employer to recognise the issues facing employees and address them by bargaining with a union.[12] In the US, this type of picketing, under Section 8(b)(7)(A) of theNational Labor Relations Act, is typically illegal if representation is not relevant or is unquestionable.[13]
In the UK mass picketing was made illegal under theTrade Disputes and Trade Unions Act 1927, moved by the leaders of what would soon be National Labour, after the1926 General Strike. Otherwise picketing was banned by theLiberal-tabledCriminal Law Amendment Act 1871 but is decriminalised by theConservative-tabledConspiracy and Protection of Property Act 1875.[14] TheTrade Union and Labour Relations (Consolidation) Act 1992 gives protection, under civil law, for pickets who are acting in connection with an industrial dispute at or near their workplace who are using their picketing peacefully to obtain or communicate information or persuading any person to work or abstain from working. However, many employers seek specificinjunctions to limit the effect of picketing by their door if they can evidence a high likelihood of intimidation or, in general, on non-peaceful behaviour and/or any that significant numbers of the picketers are or will in all likelihood be non-workers.[15]
In the US, any strike activity was hard to organise in the early 1900s, but picketing became more common after theNorris–La Guardia Act of 1932, which limited the ability of employers to gain injunctions to stop strikes, and further legislation to support the right to organise for unions. Mass picketing and secondary picketing was outlawed by the 1947Taft–Hartley Act.[16] Some kinds of pickets areconstitutionally protected.[17]
Viewing laws againststalking as potentially inconsistent with labor rights of picketing, the first anti-stalking law of the industrial world, made byCalifornia's lawmakers, inserted provisions that disapply many of its protections from "normal labor picketing", which has survived subsequent amendments.[18]