Picketing and picket lines

Find out what picketing is, when and where is picketing legal and what to do if you want to cross a picket line.

What picketing is

Picketing is used as a way of increasing support for industrial action. It is where workers involved in industrial action attend a workplace to increase support for their cause.

They might do this by communicating information or persuading others not to work or not to carry out a part of their contracts of employment. 

Picket lines

A picket line is the description given to those who gather outside or near the entrance of the workplace. These include striking workers, workers locked out by their employer and trade union representatives.

The targets of a picket line's activities may be non-striking colleagues, substitute workers or suppliers of the employer.

If you're thinking of joining a picket line, you should ask your union for advice.

Civil law and picketing

You can lawfully join a picket line as long as the picketing is:

  • connected to a trade dispute which you are involved in
  • carried out at or near your own workplace
  • carried out peacefully

If any of the above doesn't apply, an employer may be able to sue you or your union for damages under civil law.

If your employer threatens to take action against you, you should ask a solicitor for advice. Your union will have one that can act on your behalf.

Secondary picketing

If you're a worker on a picket line in dispute with your employer, you can peacefully try to persuade workers who aren't affected to support you. For example, you may try to persuade lorry drivers from a different employer not to deliver supplies. This also applies to trade union representatives lawfully present on a picket line.

However, it's unlawful to picket other companies' premises whose workers are not in dispute. For example, if you are on strike you should not go to your employer's customers' premises to encourage their workers not to handle your employers goods.

Picketing of this kind is called 'secondary picketing'. Picketing activities shouldn't interfere with workers not connected with a dispute who use the same entrance as those on strike. For example, if you work in an office block shared by different firms, you shouldn't try to picket workers from those firms.

Criminal law and picketing

It's a criminal offence for pickets to:

  • use threatening or abusive words or behave in a threatening manner towards others passing close by the picket line
  • get in the way of other people attempting to enter or leave premises being picketed
  • be in possession of an offensive weapon
  • damage property, either deliberately or recklessly
  • cause or threaten to cause a breach of the peace

There may be police present at a picket line. The police can take any measures they feel are necessary to ensure that picketing is peaceful and orderly.

Mass picketing

The chance of civil and criminal offences is higher when there is mass picketing. If there are 20 or more people on a picket line, the police can use special powers if its likely to cause serious public disorder or serious damage to property.

If the police are concerned that there's a threat to the safety of others, they can order those picketing to stop and may arrest those not complying.  Pickets and their organisers should ensure that in general the number of pickets does not exceed six at any entrance to, or exit from, a workplace.

Crossing a picket line

You have the right to cross a picket line if you don't support the industrial action being taken. If you're a union member and you're disciplined by your union for crossing a picket line, you can complain to an Industrial Tribunal.

If you're being threatened by colleagues for crossing a picket line, you should report their behaviour to the police.

If you haven't been able to cross a picket line, you need to convince your employer that you did everything reasonably possible to do so. If your employer considers you didn't make every effort, they may decide that you have joined the industrial action. This means they don't have to pay you.

Your trade union should be able to provide you with guidance on your legal obligations whilst picketing.

Where you can you get help

The Labour Relations Agency (LRA) and Advice NI offer free, confidential and impartial advice on all employment rights issues. 

If you are a member of a trade union you can get help, advice and support from them.

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