Menendez corruption and bribery case ends in mistrial: What to know

After the jury again informed the judge they could not reach a decision, a federal judge declared a mistrial in Sen. Bob Menendez's corruption and bribery trial. 

U.S. District Court Judge William H. Walls said Thursday afternoon that he found "no alternative to declaring a mistrial." 

Earlier this week, the jury told Walls that they were unable to come to a verdict, but he implored them to continue with deliberations. On Thursday, the jury again informed him of their inability to come to a decision. 

Menendez, a New Jersey Democrat, was accused of accepting a plethora of donations and gifts from a wealthy friend in exchange for political influence. Both Menendez and the doctor, Salomon Melgen, maintained their innocence. 

This was the first time in nine years that a sitting U.S. senator faced federal bribery charges.

What was Menendez accused of?

Menendez, 63, accepted an abundance of campaign donations, gifts and vacations from Salomon Melgen, a Florida ophthalmologist, according to prosecutors. In return, prosecutors claimed, he used his position to lobby on behalf of Melgen’s business interests.

Melgen allegedly directed more than $750,000 in campaign contributions to entities that supported Menendez, according to the indictment, which prosecutors said were inducements to get Menendez to use his influence on Melgen's behalf. Prosecutors have also accused Menendez of trying to hide the gifts.

Sen. Bob Menendez, center, arrives to the courthouse with his children, Alicia Menendez and Robert Menendez Jr., in Newark, N.J., Wednesday, Sept. 6, 2017. The corruption trial for the New Jersey Democrat and a wealthy Florida eye doctor begins on Wednesday in Newark. The trial will examine whether Menendez was illegally lobbying for Salomon Melgen, who gave him political contributions and gifts including luxury vacations. (AP Photo/Seth Wenig)

Sen. Bob Menendez, D-N.J., arrives to the courthouse with his children in Newark, N.J., on Sept. 6, 2017 as the corruption trial begins.  (AP Photo/Seth Wenig)

Melgen paid for Menendez and his girlfriend to stay for three nights at a Parisian hotel where rooms typically cost about $1,500 per night and allowed the senator the use of his private jet, according to prosecutors.

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Federal prosecutors said that Menendez “sold his office for a lifestyle that he couldn’t afford.”

The indictment also alleged that Menendez pressured State Department officials to give visas to three young women described as Melgen's girlfriends.

What was the senator’s defense?

Both Menendez and Melgen pleaded not guilty – and Menendez has vehemently denied the accusations against him.

Throughout the trial, defense attorneys sought to prove that Menendez and Melgen have been friends since before the former became a senator, and the trips were nothing more than friends traveling together.

At times emotional, Menendez maintained his innocence.

What happened during the trial?

Defense attorney Raymond Brown got into a spat with Walls at the start of the trial. Brown accused Walls of being “extremely prejudicial to the defense.”

Walls had denied Menendez’s request that the trial be recessed during critical Senate votes, stating that his job should not be treated differently from that of a construction worker or cab driver.

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The trial focused on a meeting former Senate Majority Leader Harry Reid, D-Nev., set up with Menendez and former Health and Human Services Secretary Kathleen Sebelius to discuss a nearly $9 million Medicaid billing dispute.

Sebelius testified in court that the incident was the first time in her role in government that she was asked by a senator to take a meeting with another senator. She said that Melgen wasn’t specifically mentioned in the meeting but that she assumed his case was the topic.

Walls declined to throw the case out despite the defense’s objections that the accusations against Menendez didn’t fit the narrow definition of bribery that was a result of a 2016 Supreme Court decision.

Menendez also had a little help from his friends.

Sen. Lindsey Graham, R-S.C., went to the Newark courthouse to testify as a “character witness” for the Democratic senator, Graham’s office confirmed. He testified about his experiences with Menendez in the Senate, “unrelated to the underlying charges,” his office said.

"In very difficult circumstances he always keeps his word," Graham, said during his testimony. "A handshake is all you need from Bob. He's a very honest, hardworking senator."

Sen. Corey Booker, D-N.J., also appeared in support of Menendez. 

Menendez was also emotional when he was asked by reporters about his colleagues’ support. 

Is there anything else to know about Salomon Melgen?

Melgen, 63, was convicted of 67 counts of health care fraud in April in what the Palm Beach Post called one of the biggest Medicare fraud cases in the U.S.

During that case, prosecutors argued that Melgen, who was born in the Dominican Republic, robbed Medicare of as much as $105 million, according to the newspaper. His sentencing has been delayed until after this trial.

Florida ophthalmologist Salomon Melgen arrives to the Federal court in Newark, New Jersey April 2, 2015. U.S. Senator Robert Menendez of New Jersey was indicted on corruption charges, allegations that the high-ranking Democrat vowed to fight at a news conference on Wednesday night. Menendez was indicted by a grand jury in New Jersey for accepting gifts from Melgen in exchange for using the power of his Senate office to benefit Melgen's financial and personal interests, according to the court filing. REUTERS/Eduardo Munoz - GF10000047382

Florida ophthalmologist Salomon Melgen is accused of giving Sen. Bob Menendez, D-N.J., gifts in exchange for help with his personal and financial dealings.  (Reuters/Eduardo Munoz)

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Aside from Menendez, Melgen has given significant amounts of money to a variety of Democratic lawmakers, according to public records.

What would have happened if Menendez was convicted?

If Menendez was convicted and sentenced to prison, Gov. Chris Christie, R-N.J., would have picked a replacement.

That prospect was troublesome for Democrats who fear that Christie would have picked a Republican to fill the Senate seat – giving the GOP an additional edge for legislative fights.

Vice President Mike Pence had said that it would be "altogether inappropriate and wrong" for a convicted felon to remain in the Senate. However, he said it would be a decision left up to the Senate if Menendez didn't resign.

Menendez is up for reelection next year. He was selected to replace former Gov. Jon Corzine, D-N.J., in the Senate in 2005.

The most serious charges against the two men carried a maximum 20-year prison sentence.

Fox News’ Tara Prindiville and The Associated Press contributed to this report.

Kaitlyn Schallhorn is a Reporter for Fox News. Follow her on Twitter @K_Schallhorn.