Every Israeli prime minister since 1996 has been the subject of a corruption investigation.

Benjamin Netanyahu, Ehud Olmert, Ariel Sharon and Ehud Barak have all been investigated for graft, along with several cabinet ministers, Knesset members and mayors.

Here's a look at some of the major corruption scandals to have rocked Israeli politics over the past two decades, and the big names involved.

Benjamin Netanyahu

Benjamin Netanyahu has been plagued by a string of corruption scandals during his two terms in office.

During his first spell as prime minister from 1996-1999, Netanyahu was investigated for a variety of reasons, including a kickback scheme and influence-peddling.

He is currently the subject of two separate police investigations - dubbed cases "1,000" and "2,000" - in which, if he is found guilty, he would almost certainly be sent to prison.

The first case relates to gifts worth nearly $300,000 given to him and his family by two business tycoons, allegedly in exchange for political favours.

Australian billionaire James Packer along with former secret Israeli agent Arnon Milchan are alleged to have courted Netanyahu, his wife Sara and son Yair, with expensive champagne, cigars and jewelry.

Netanyahu does not deny accepting the gifts, but refutes claims he returned any favours.

In the second investigation, police allege Netanyahu tried to strike a deal with the country's second-largest newspaper Yedioth Ahronoth, that he would support legislation designed to hurt their main competitor, Israel Hayom, in exchange for positive press coverage.

Netanyahu is also expected to give testimony as part of "Case 3,000", the most serious scandal swirling around the prime minister.

Though he is not a suspect in this investigation, which involves alleged corruption in the sale of German submarines and naval attack vessels worth $2bn, his cousin and personal lawyer David Shimron is.

In Case "4,000," Netanyahu's associate Shlomo Filber, director-general of Israel's Communications Ministry, is accused of providing Bezeq, the national telephone company, with favourable treatment.

He is also not a suspect in this case, although the attorney-general could take action with respect to apparently "false declarations".

Meanwhile, Netanyahu's wife Sara is likely to be indicted for misusing public funds.

The first lady is accused of fraudulently diverting some $100,000 of the public purse to pay for private chefs at family events, furnish and improve their private home in Caesarea, and to pay for the personal care of Sara's father.

Ehud Olmert

Ehud Olmert, who served as prime minister from 2006-2009, is currently serving an 18-month prison sentence for fraud, breach of trust, falsifying corporate records, and tax evasion.

He was charged just five months after he left office and convicted of taking bribes of about $430,000 in relation to a housing project in Jerusalem while he served as mayor.

But even before the conviction, Olmert's political life was dogged by allegations of financial impropriety.

In 1996, he was tried on charges of breaking Israeli law on party funding, although he was eventually cleared.

He was later investigated on suspicion of accepting bribes from a businessman during the so-called Greek Island affair, although prosecutors dropped the charges because of a lack of evidence.

Ariel Sharon

Ariel Sharon, who served as prime minister from 2001-2006, was accused of taking hundreds of thousands of dollars in bribes in the late 1990s in what came to be known as the Greek Island affair.

Prosecutors said Israeli businessman David Appel paid Sharon's son Gilad large sums of money to persuade his father, then foreign minister, to promote real estate deals - including one on the Greek island resort of Patroklos - that was never built.

Sharon escaped corruption charges after the attorney-general decided there was not enough evidence against him.

Ehud Barak

Ehud Barak, who served as prime minister from 1999-2001, was investigated on several occasions on allegations of illegal campaign financing, bribery and money laundering.

Police ended their probe in 2003, citing a lack of evidence, and in 2006 the State Attorney's Office announced the investigation had been closed without any indictments.

Ezer Weizman

Ezer Weizman, who served as president from 1993-2000, stepped down early after prosecutors said he accepted more than $300,000 from two executives.

However Weizman - a nephew of Chaim Weizmann, Israel's first president - escaped prosecution because the statute of limitations had elapsed.

Avigdor Lieberman

Avigdor Lieberman, the current defence minister, was cleared by an Israeli court in 2013 on charges of fraud and breach of trust.

Lieberman, who has made several incendiary statements about Palestinians, was unanimously acquitted by a panel of three judges in a hearing that lasted just a few minutes.