Chuckers are considered cheats. On the other hand, a batsman at the non-strikers end, who has been repeatedly warned by the bowler with the knowledge of the umpire, but persists in taking early starts, is considered to be "dozy" for "wandering out of his crease". While some stray enlightened writers have asserted that Jos Buttler was cheating - deliberately defying the law - to gain the advantage of a couple of feet, most writers who agree that Angelo Matthews was right, are unwilling to attribute anything other than distraction or absentmindedness to Buttler's conduct.
Bowlers have no such luck. A chucker is a cheat is a chucker. Chucking is a technical offense. Especially when a bowler's stock action, or his typical action for a variation turns out to be illegal, it is palpably not a matter of cheating. Unless the claim is that the bowler is existentially a cheat - that since the age of 12 or 15 or whenever the bowler learnt to bowl, there has been a concerted effort by the player's mentors to produce a competitor on the margins of the law. Even here, it is not clear how this is the bowler's fault.
Throwing is a technical offense, just like bowling any other type of no ball (high or otherwise) is a technical offense. It ought to be treated as such. One of the downsides of Arjuna Ranatunga's aggressive conduct in Australia in the mid-nineties has been that umpires don't call bowlers for throwing anymore. It is not clear that this is in accordance with the law.
There are three regulations which apply here.
1. Law 24 of the Laws of Cricket (see 24.2, 24.3)
2. The ICC's ODI Playing conditions for 2013-14 (see p 4.19)
3. The ICC's regulations for the review of bowlers with suspected illegal bowling actions
Law 24.3 defines a fair delivery as follows:
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. This definition shall not debar a bowler from flexing or rotating the wrist in the delivery swing.Note that this rule does not expect that the bowling arm will not already be bent at the elbow when it reaches the level of shoulder in the swing. What it does not permit, is straightening after this point. This is perhaps the most common misunderstanding about the the rule. A fair delivery does not require a straight arm. It only requires that the angle at the elbow not change (with caveats) after the delivery swing has reach the level of the shoulder.
The regulations for review contain an explanatory appendix which describes the difference between flexion and extension, and the existence of hyperextension (and abduction and adduction). The 15 degree threshold does not exist because of any biomechanical reason. This is to say that it does not exist because it has been established that beyond 15 degrees, the bowler gains an unfair advantage (in terms of generating speed or accuracy for example). As this report from 2004 indicates, the 15 degree threshold exists because it has been found that the human eye typically cannot detect flexion if it is under 15 degrees. With some bowlers, we do notice the kink in the arm - hence the suspicion that the 15 degree threshold is crossed. What remains to be assessed during the review is where this kink in the arm comes from - if some of it can be explained due to some degree of hyper-extension (along either axis), and the residual bend is under 15 degrees, then the bowler is not throwing.
With this in mind, let's revisit the law. The current law, as written, requires that the umpire call a bowler for chucking on the field. Law 24(2)(a) leaves no room for doubt.
(a) If, in the opinion of either umpire, the ball has been thrown, he shall call and signal No ball and, when the ball is dead, inform the other umpire of the reason for the call.In recent years, Umpires have stopped doing this. Their usual practice has been to report the bowler after the game. The ICC has laid out a precise procedure for doing this in which it describes the type of evidence which umpires must provide. The ICC's regulations for reviewing actions do not affect Law 24 at all. They apply if "a Player is called by an Umpire under the provisions of Law 24.2 or is suspected by an Umpire or the Match Referee of bowling with an Illegal Bowling Action"
However, an umpire has no discretion under Law 24 to "suspect" an illegal action. Any such suspicion must be backed up by a call of "no-ball". A legal delivery in cricket is not defined other than in the context of a no-ball. It does not fall under the category of unfair play (ball tampering does). In fact, Law 42 explicitly limits the authority of umpires to act according to the Laws. Clause 42(2):
The umpires shall be the sole judges of fair and unfair play. If either umpire considers an action, not covered by the Laws, to be unfair he shall intervene without appeal and, if the ball is in play, call and signal Dead ball and implement the procedure as set out in 18 below. Otherwise umpires shall not interfere with the progress of play without appeal except as required to do so by the Laws.The emphasis is mine.
During a cricket match, except under special, well-defined circumstances (such as a 2nd high full toss or intimidatory bowling or batsmen running on the pitch), the Umpire's authority is limited to specific events occuring during a discrete play. The Umpire has no authority and there are no Laws in cricket which allow an umpire to pass general judgment on any aspect of play. The ICC's reporting procedure, on the other hand, requires that Umpires report players for "bowling with an illegal bowling action". They are not required, under the reporting procedure, to specify which deliveries in particular (the 4th ball of the 26th over, for example) caused the umpire to suspect the legality of the bowling action. At most, they ask that the umpire specify types of deliveries (googly, doosra, faster one, bouncer etc.) which look suspicious. As if this was not enough, a video record of the bowler's spell has to be attached with the report.
Law 24 is designed to be applied to individual deliveries. Under the ICC's regulations, it is now applied to a "bowling action". This is a difficult problem. However, given the way the rules are written, Senanayake could argue (persuasively in my view), that since he was never called in the game in which he was reported, the reporting procedure was not followed properly. This along with the more common argument that Senanayake has been played First Class Cricket since 2006 and international cricket since January 2012, dozens of international umpires have observed him and he has never been called for throwing over nearly 2000 deliveries in international cricket, would make it difficult for the ICC to consider that he had been reported properly.
The apparent proliferation of illegal actions in international cricket which was discussed in a recent meeting of the ICC's Cricket Committee, is mainly because Umpires have not been calling bowlers for delivering no-balls. They have not been applying Law 24. This has made throwing into a moral offense, rather than a technical one. If bowlers were called for throwing more regularly, it would take the sting out of the law, and it would also encourage teams to not pick these bowlers. This would have a huge effect on reducing the number of bowlers with illegal actions in cricket.
Senanayake may well have an illegal bowling action. Currently, because of the Umpires' unwillingness to call bowlers for throwing, it is not clear whether the ICC can do anything about it under their own rules.
As for the problem of chucking, if the ICC wants to police actions, perhaps it will be better to require all bowlers to submit to a test similar to the one suspected bowlers currently undergo, within their first year in international cricket. This will provide benchmarks. This is the only way to check something as general as a bowling action (as opposed to the way one delivery is bowled) fairly.