Specialists divided corruption into different categories, such as financial , administrative, political, social and economical corruption. Also it was divided into grand and petty corruption. Entities , which concerned to fight corruption, were usually involved to pursue grand corruption by pursuing the petty corruption , so what are the standards to distinct grand and petty corruption?
Many criteria can be used to distinct grand corruption , they are;-

1.  Value of corruption:- whenever the finance value of corruption was grand so the corruption was grand ,too. So if the amount of bribery or embezzlement was grand, the crime would be grand .If not, the corruption would be petty. Regardless if corruption was committed by high-ranking official or minor one. If the minister bribed or embezzled small amount, the corruption considered small. But if a minor official bribed or embezzled big amount, the corruption considered grand . But this standard faces many difficulties specially in corruption cases that we can not estimate their values such as when the bribe is sexual activity , in this case we can not estimate the amount. So it would be impossible to estimate the value of such kind of bribe , as well as with cases deals with actions that causes damages, intentionally or with negligence, with public money and in the case of appointing relatives .
2. Position of the corruptor :- Corruption will be grand if the corruptor occupy high level rank like minister or deputy minister or member of parliament . Corruption will be petty if the corruptor is minor regardless of the value of corruption. This standard looks much easier and clearer in application , but it needs to set clear regulations to determine the high and low positions which themselves have different standards and criteria. So we can consider employees who occupy supervision or commanding positions as high ranking officials , while employees who don`t occupy supervision or commanding positions can be considered regular officials . New standards may be applied to determine the high ranking officials when they get appoint in the future , for example when someone get appoint by republican decree or depend on the authority of appointment. So the official considers a high ranking one if the legislative authority interferes in his appointment or when they authenticate his appointment . Or may be a new standard will be put into use when they determine the importance and risk of the role those officials play. Hence we can not consider the investigator as a high ranking official depending on the above mentioned regulations , but he will be consider a high ranking official depending on the standard of the seriousness role that the public official practice .
3.  The Public Opinion: Corruption cases are sorted as of grand corruption only when they create a center of attention of the public opinion, nevertheless they are committed by major or minor officials, nor the corrupt money is big or small amounts.
4. Importance of the Sector: Cases are considered of grand corruption when their targets are the most important state sectors, just like corruption occur within the oil sectors in the petroleum countries, in which the oil is the pulse of their economy life. And that is also true to corruption occurring in the sectors of justice, education or health.
5. Corruption Effects: Also corruption is deemed grand when it has dangerous effects on society, nevertheless how much the corrupt amounts of money are, or how much the positions of the corrupts are high. Infiltrating tests to the students by a professor in university is of a grand corruption for it has dangerous effects on the education process, also corrupt judges, even gain small amounts, are more dangerous than a major corrupt administrative employee gain big amounts from corruption practices.
6. Corruption as a phenomenon: Briberies of small amounts of money daily taken by minor employees working on the entities providing public services like: passports issuing offices, drive licenses offices, real estate registration offices, traffic office and municipality office etc. are considered of small corruption, but at the same time, they are as grand corruption for their dangerous spreading amongst employees and become as a phenomenon.
7. Corruption takes havens: Because of certain political and social circumstances, some of corrupted practices find haven, gust like corruption committed by some of the senior official dominate the countries such as high ranks officials, chiefs of tribes and sects. Such corruption is of grand ones.
8. Legally recognized Corruption: Some of the corruption forms come out of enacting laws such as the regulations that over increased the salaries of senior state officials and granted them very high pensions regardless the number of years they should served in their positions. Also these regulations gave huge undeserved privileges to the ministers and to the legislative authority members and others. So, corruption recognized by laws is grand corruption.
9. Criminating Corruption: Corruption either be criminated or incriminated. Being late in daily work is one the corruption forms but it is incriminated by laws, while bribery or embezzlement is criminated by obvious penalty provisions in laws. So, the criminated corruption is a grand corruption and the incriminated corruption is small corruption. However, criminating and incriminating some practices is view of looking to them from the national laws point of view or from the UNCAC point of view, some of the corruption forms are incriminated by national laws like bribery or embezzlement in private sectors but the UNCAC criminates those forms of corruption.
10. Corruption in Big Projects: corruption may occur in preparing, awarding or implementing the strategic projects is grand corruption.  
11. Corruption in Elections: Buying votes, forging results and the illegal financing the election campaigns are of the most dangerous cases of corruption because it falsifies the will of people and wastes the principles of the democratic system.
12. The importance of institutions: like corruption in monitoring authorities and entities (legislative and judiciary authorities) , bribing judiciary even with small amounts is considered the most dangerous form of bribery and the abuse of power by parliaments is the most dangerous form of abuse, because it is made by people occupying positions in the strongest monitoring authorities.
13. Practices generating corruption: some forms of corruption are exceeding the meaning of corruption to be the basis for deeper one. The appointment in the leading positions on the base of favoritism, nepotism, section and party irrespective to integrity and efficiency standards is considered corruption result in another deeper corruption. When a person, who is inefficient and not honest, is appointed in important position, this will be the beginning of bigger and more dangerous corruption.
14. Evidences availability: corruption is considered grand if it is supported by availability of strong evidences and it is small when there are weak evidences that do not fit to trail those who committed it.

The above mentioned are the most important criteria of distinguishing grand corruption and all are fit to be adopted even though it is difficult to put them all under one criterion. Some of them are dependable in the real field of work to trail corruption crimes.

 In COI we depended on only four criteria of the above mentioned ones:

 1. The volume of corruption value.
2. How high is the position of the person accused of corruption?
3. Public opinion interest.
4. Evidences availability. The four criteria are used by investigators to determine which cases are important and need to be focused on according to rules of investigation office issued under the name of receiving and investigating corruption allegations.

 Judge: Raheem Hassan Al Ugaily
COI Commissioner         
August 2010