Purpose
Generally, the purpose of altering the state of the ball is to achieve more favorable bowling conditions. A fielder may apply a substance, such as lip balm or sweetened saliva, to shine one side of the ball or pick the seam of the ball to encourage more swing. Conversely, one side of the ball can be roughened by use of an abrasive or cutting surface (such as boot spikes or bottle caps). The use of sweetened saliva was shown to be particularly useful in obtaining Reverse swing in the 2005 Ashes series
Altering a Ball Legally
Using spit and/or sweat is common and, for practitioners of swing bowling, integral. The moisture gained from spit or sweat when combined with polishing, smooths out one half of the ball which in turn allows air to pass over one side of the ball quicker than the other. When bowled correctly, a bowler can get the ball to move from one side to the other through the air. Also, it is not unusual for bowlers to rub the ball against their legs to clean it as it has been seen in almost every cricket match. ,.
Sanction
The umpires are responsible for monitoring the condition of the ball, and must inspect it regularly. Where an umpire has deemed a fielder to be guilty of ball-tampering, five penalty runs are awarded to the batting side, and the ball must be immediately replaced. The replaced ball is normally chosen by the umpires, in which case the ball chosen should match the condition of the previous ball (before tampering) as closely as possible. Depending on additional agreements laid out before the beginning of a series of matches, the batsmen may be instead permitted to choose the ball from a selection of balls in various stages of use.
A bowler guilty of ball-tampering can be prohibited from continuing to bowl in that innings if he is found to be repeatedly ball-tampering. Following the conclusion of play, additional sanctions are usually brought against a ball-tamperer, as it is considered a serious offense. The captain may be equally penalized, as he is responsible for the conduct of his players on the field.
Examples
The use of foreign substances to polish the ball, while illegal, is in some corners considered to be relatively common, and passes without incident or sanction. Substances which are suggested for this purpose include hair gel, sugar and lip balm.
In addition, picking at the threads of the main seam or 'lifting' the quarter seam to aid conventional and reverse swing respectively are considered illegal. Modifying the quarter seam can be particularly difficult to detect or prove.
However, there have been a number of high-profile instances of ball tampering, particularly in international cricket due to the increase in television coverage. The Pakistani cricket team were arguably the first to come under scrutiny, when they were together in 1992 accused of ball-tampering to achieve large amounts of reverse swing. However, no evidence of wrongdoing was ever found in that series. Because of these allegations, in 1996, Imran Khan sued Ian Botham for slander and libel in a British court, and was awarded £400,000.
Then England captain Michael Atherton was accused of ball tampering during the a Test match with South Africa at Lord's in 1994 after television cameras caught Atherton reaching into his pocket and then rubbing a substance on the ball. Atherton denied ball tampering, claiming that he had dirt in his pocket which he used to dry his hands. Atherton was summoned to the match referee and was fined £2,000 for failing to disclose the dirt to the match referee.
Waqar Younis became the first player to receive a suspension for ball-tampering after a match in 2000.
In January 2004, India's Rahul Dravid was fined after he rubbed a half-eaten lolly onto one side of the ball during an ODI. Such instances of using sweetened saliva are not uncommon, as many players claim that the sugary saliva caused by eating confectionery is more effective in polishing the ball than normal saliva. Marcus Trescothick claimed in his autobiography that England's players achieved their prodigious amounts of reverse swing in their successful 2005 Ashes series against Australia by using saliva sweetened by eating mints.
Similarly, some believe[says who?] that greasy hair products and sunscreen, can mix with perspiration and the resulting oily liquid is more effective in polishing the ball.
