In England and Wales, the sus law (from "suspected person", see below) was the informal name for a stop and search law that permitted a police officer to stop, search and potentially arrest people on suspicion of them being in breach of section 4 of the Vagrancy Act 1824.
The power to act on "sus" was found in part of section 4 of the Vagrancy Act 1824, which provided that:
every suspected person or reputed thief, frequenting any river, canal, or navigable stream, dock, or basin, or any quay, wharf, or warehouse near or adjoining thereto, or any street, highway, or avenue leading thereto, or any place of public resort, or any avenue leading thereto, or any street, or any highway or any place adjacent to a street or highway; with intent to commit an arrestable offence— section 4, Vagrancy Act 1824
"shall be deemed a rogue and vagabond" and would be guilty of an offence, and be liable to be imprisoned for up to three months. This effectively permitted the police to stop and search, and even arrest, anyone found in a public place on the grounds that they suspected that they might intend to commit an offence.
In order to bring a prosecution under the Act, the police had to prove that the defendant had committed two acts:
- the first, that established them as a "suspected person" (by acting suspiciously), and
- the second, that provided intent to commit an arrestable offence.
Two witnesses were required to substantiate the charge, which was usually two police officers patrolling together.
The law caused much discontent among certain sections of the population, particularly black and ethnic minorities, against whom the law was particularly targeted by the police—see racial profiling. The sus law had attracted considerable controversy prior to the early 1980s race riots (in St Pauls, Bristol, in 1980, and in Brixton, London, Toxteth, Liverpool, Handsworth, Birmingham and Chapeltown, Leeds in 1981). In 1980, the House of Commons' Sub-Committee on Race Relations and Immigration began hearings into the law. In the case of the race riots, its alleged abuse was believed to be a contributory factor to those events. The sus law was repealed on 27 August 1981, on the advice of the 1979 Royal Commission on Criminal Procedure, when the Criminal Attempts Act 1981 received Royal Assent.
Subsequent British legislation that makes provision for the police to act on the basis of suspicion alone has been denounced as "another sus law" by opponents of proposals to grant increased "stop and question" powers to police officers in England and Wales.  Scottish law permits detention without arrest for up to six hours, using powers under the Criminal Justice (Scotland) Act 1980.
Mr Hain said he wanted to see the details of the policy before making any judgement. But he told BBC1’s Sunday AM: “We cannot have a reincarnation of the old ‘sus’ laws under which mostly black people, ethnic minorities, were literally stopped on sight and that created a really bad atmosphere and an erosion of civil liberties.”
In January 2008 David Cameron, at the time Leader of the Conservative Party, announced that he would, if elected, seek to return similar powers to the police. Under Conservative proposals, police sergeants would be able to authorise the use of stop and search of pedestrians and vehicles in a specific area for up to six hours—or 48 hours if permission is granted by a senior officer. Gordon Brown, Labour Party Leader and Prime Minister at that time, announced, in response that he would seek to remove the lengthy forms that are currently required for 'stop and searches'.
- "sus | suss, n.". Oxford English Dictionary. Oxford University Press. Retrieved 20 April 2011.
- "The legacy of the Brixton riots". BBC News. 5 April 2006. Retrieved 2007-06-06.
- Terrill, Richard J (Summer 1989). "Margaret Thatcher's Law and Order Agenda". The American Journal of Comparative Law 37 (3): 429–456. Retrieved 20 April 2011.
- section 8, Criminal Attempts Act 1981, by section 11 (commencement), one month after date of assent
- "Concerns voiced over new terror powers". The Times (London). 27 May 2007. Retrieved 2007-06-06.
- "Reaction to 'stop and question' plans". BBC News. 27 May 2007. Retrieved 2 March 2015.
- "Concern over new anti-terror laws". Metro. 27 May 2007. Retrieved 2 March 2015.
- "Push for new stop and search laws". BBC News. 30 January 2008. Retrieved 24 May 2010.