South African businessman Schabir Shaik has pleaded not guilty to charges of bribery, fraud, and corruption at the start of his long-awaited criminal trial. The case is linked to Deputy President Jacob Zuma, whose political future could be at stake over the verdict.

As South Africa's biggest post-apartheid corruption trial gets underway, the spotlight is on one man who is not even in the courtroom, Deputy President Jacob Zuma.

The accused, Schabir Shaik, is the deputy president's close friend and financial advisor. All of the charges against Mr. Shaik have to do with Mr. Zuma, who is not only the second-most powerful politician in the country, but also seen as one of the frontrunners to become South Africa's next president.

Mr. Shaik is accused of paying Mr. Zuma more than $186,000 dollars in bribes. He is also charged with soliciting a yearly payment of about 75 thousand dollars for the deputy president from a French arms company, in connection with an already controversial government arms deal.

In an opening statement read by his lawyer, Mr. Shaik admitted making payments to Mr. Zuma and members of his family. But he said they were loans. And he says the deputy president signed an agreement expressing his intent to pay the money back.

Last year, the national director of public prosecutions said he lacked enough evidence to bring the deputy president to trial. But he refused to rule out prosecuting Mr. Zuma later, saying that new evidence could emerge during Mr. Shaik's trial.

As the trial got underway in Durban, Judge Hillary Squires made it clear to the packed courtroom that Mr. Zuma is not on trial, and that the case is not a commission of inquiry into the arms deal.

But despite that warning, the trial is seen as crucial for the deputy president. Senior analyst Steven Friedman of the Center for Policy Studies says Mr. Zuma's political future may be at stake no matter what the verdict is.

"Assuming there is evidence against Mr. Zuma this could be a very important test," he said. "Of course, if there is not any evidence against Mr. Zuma, this is still an interesting trial because the effect of there not being any evidence against him would be to immensely strengthen his already-strong position in the race to be the next president."

Mr. Friedman says the trial has immense political significance because of Mr. Shaik's ties to the deputy president. He also says the decision about whether or not to prosecute Mr. Zuma may have consequences for the South African judicial system.

"I think they were making quite an interesting point about our new democracy, which is that this is the first time in the history of South Africa, in over 300 years, that we have had institutions and systems which really call senior politicians to account," he added. "These systems are quite fragile. It is a new experience for the country, and it was clearly the view of the national prosecuting authority that unless you have an absolutely watertight, cast-iron case, it would be unwise to act against the deputy president because if the prosecution failed through want of evidence, it would be a serious setback for the credibility of the criminal justice system."

Most of the charges against Mr. Shaik deal with financial activity between 1995 and 2002. More than 100 witnesses from 10 countries are slated to testify, but Deputy President Zuma is not expected to be one of them.