“Throwing” down the gauntlet: What constitutes an illegal delivery in cricket?

The issue of legality of bowling actions in cricket came to the fore again during the recent ICC World Twenty 20 tournament in India. Two frontline bowlers for Bangladesh - Taskin Ahmed and Arafat Sunny - were suspended after their bowling actions were deemed illegal.¹ This followed the suspension and subsequent reinstatement of West Indies off-spinner Sunil Narine for suspect deliveries bowled during the third One Day International against Sri Lanka on 7 November 2015 in Pallekele.²

In light of these recent controversies, this article examines the Laws of Cricket³ (“Laws”) and ICC Regulations for the Review of Bowlers reported with Suspected Illegal Bowling Actions to explain exactly what does and does not constitute a fair delivery in cricket, and how the review and assessment procedure operates. 

The Laws of Cricket

The rules on what constitutes a fair delivery have changed over time. In 1816, the Laws stated, “the ball must be delivered underhand…with the hand below the elbow.”⁴ In 1806, Kent player John Willes is said to have been the first to bowl the “round arm” delivery at Lord’s, “using a sort of low slinging motion.” The Marylebone Cricket Club (MCC) called such an action “throwing” and initially tried to outlaw it. However, the popularity of round-arm bowling won through and it was legalized in 1835.⁵ 

While taking their inspiration from Willes, today’s bowling actions have developed significantly, as have the Laws governing their legality. The MCC is recognized as the sole authority for drafting the Laws, and has been since its formation in 1787.⁶ When amending the Laws, the MCC consults the game’s stakeholders, including all the Full Member Countries of the International Cricket Council (ICC), which is the global governing body for cricket.⁷

The relevant Law governing bowling actions is Law 24 (No Ball). Law 24.2 sets out what is a “Fair Delivery” in respect of the arm (the feet are dealt with under Law 24.5). The Law simply states that,

“For a delivery to be fair in respect of the arm the ball must not be thrown. See [Law 24.3] below”

Law 24.3 “Definition of Fair Delivery – the arm” continues to state,

“A ball is fairly delivered in respect of the arm if, once the bowler’s arm has reached the level of the shoulder in the delivery swing, the elbow joint is not straightened partially or completely from that point until the ball has left the hand.”⁸

Law 24 has been adopted in the playing conditions of the three most popular formats of the game:

• Standard Test Match Playing Conditions(clause 24.1); and
• Standard One-Day International Playing Conditions of the ICC(clause 24.1),
• Standard Twenty20 International Match Playing Conditions (clause 24.1).

The Law does not restrict a bowler from flexing or rotating the wrist in the delivery swing. Rather, it was designed to ensure that the bowler did not gain an unfair advantage by “throwing” the ball (or “chucking” it, in informal terms), because an elbow extension while delivering the ball may impart extra speed to the delivery.⁹

However, the Law has proved somewhat controversial. The ICC soon realized that, due to various physiological reasons, most bowlers’ arms straightened to different degrees when delivering the ball. Accordingly, if the Law – which requires “the elbow joint not [to be] straightened partially or completely” – was operated strictly, a significant number bowling actions would be deemed “illegal”.

As a result, the ICC amended the rule by permitting acceptable ranges of elbow extension (or “flex”) depending upon the bowler’s delivery type:

• 10 degrees for fast bowlers,
• 7.5 degrees for medium-pacers, and
• 5 degrees for spinners.¹⁰

The amended test did not last for long though. Its limitations were highlighted in the relatively well know case of Sri Lankan player, Muttiah Muralitharan.¹¹ Muralitharan was called for “throwing” several times. Biomechanical laboratory tests were conducted in Australia and the degree of flex in his arm was measured at around 10 degrees. Muralitharan argued that while spinners were allowed only 5 degrees of flex, his action should be legal because it should be the speed of the arm that determined the permitted degree of flex, and not the speed of the delivery. He stated that his “arm speed is fast as a fast bowler” and the tests confirmed it.¹² What appeared to be an “illegal” action to the naked eye was in fact “legal”.

Further refinement was needed. In 2004, the ICC Cricket Committee constituted a panel comprising of Angus Fraser, Aravinda de Silva, Dave Richardson, Michael Holding, Sunil Gavaskar, Tim May and Tony Lewis to review and amend the test to make it more uniform. After consideration, the panel recommended a maximum of 15 degrees of flex to be allowed no matter what the style of the bowler. The 15-degree limit was chosen because, according to panel member Fraser, “that is the number which biomechanics says that it (straightening) becomes visible.”¹³ The rule was approved and came into effect from March 1, 2005.¹⁴

The ICC Regulations for the Review of Bowlers reported with Suspected Illegal Bowling Actions