The burden of proof (Latin: onus probandi) is the obligation to shift the accepted conclusion away from an oppositional opinion to one's own position.

The burden of proof is often associated with the Latin maxim semper necessitas probandi incumbit ei qui agit, the best translation of which seems to be: "the necessity of proof always lies with the person who lays charges."

He who does not carry the burden of proof carries the benefit of assumption, meaning he needs no evidence to support his claim. Fulfilling the burden of proof effectively captures the benefit of assumption, passing the burden of proof off to another party.

A "legal burden" or a "burden of persuasion" is an obligation that remains on a single party for the duration of the claim. Once the burden has been entirely discharged to the satisfaction of the trier of fact, the party carrying the burden will succeed in its claim. For example, the presumption of innocence places a legal burden upon the prosecution to prove all elements of the offense (generally beyond a reasonable doubt) and to disprove all the defenses except for affirmative defenses in which the proof of non-existence of all affirmative defense(s) is not constitutionally required of the prosecution.

Burden of proof may refer to:

Sussex Police is the territorial police force responsible for policing East Sussex, West Sussex and City of Brighton and Hove in southern England. Its Headquarters is in Lewes, Lewes District, East Sussex.

Policing in the county can be traced back to the first force established in Brighton in 1830. A few years later on 13 March 1844 Chief Constable Henry Solomon was murdered in his office by a prisoner he was interviewing. He is believed to be the only chief officer to have suffered such a fate. Prior to 1830 local watchmen were appointed to provide some degree of law enforcement in the area. In 1812, there were some 12 watchmen who were responsible for the town. By 1814 the number had grown to 28 and at this time the title of constable was in use for them. By 1868 the force had grown to 100 officers and helmets replaced top hats.

In 1918 the first woman was appointed as a police officer in this force and by 1930 it had grown to 216 officers. Brighton Police were the first force to introduce police radios on the 14th September 1933. Forces were also established for the counties of East Sussex and West Sussex, as well as separate forces in the boroughs of Brighton, Eastbourne and Hastings. These forces amalgamated temporarily during the Second World War, from 1943 until 1947, but then policing reverted back to the old system for another two decades.