Donald Trump's business empire is in a battle with prosecutors over three words that could affect the company's tax fraud trial.

Three words are used.

That isn't a mistake.

It's "in behalf of", not "on behalf of", a musty-sounding phrase that has smart and seasoned lawyers on both sides of the case reaching for legal treatises, decades-old case law, and even merriam-webster.com as they

The jury at the New York Supreme Court in lower Manhattan has barely heard any references to the words.

Each of the 15 criminal charges against the Trump Organization alleges that the former president's real-estate and golf-resort company colluded with its own top financial executives to avoid taxes.

When testimony ends in mid-December, New York Supreme Court Justice Juan Merchan will give instructions to jurors on how to reach a verdict.

They will be told that it's not enough for Trump executives to be greedy.

To find the Trump Organization guilty of fraud, the jury must find that its executives not only broke the law but did so while acting within the scope of his or her employment.

But a nagging and very reasonable question remains unanswered, and it's only a matter of time before it's posed by jurors themselves.

The judge has yet to figure it out.

"We don't know how we will tell them if they ask for additional instructions," the New York Supreme Court Justice said before testimony began.

The tax dodge is the easy part 

The first element of the law in deciding if the company, too, is guilty is the guilt of the two top money men.

The scheme was admitted by both men.

The former CFO, Allen Weisselberg, pleaded guilty in August to conspiring with the company's top payroll guy to hide hundreds of thousands of dollars in executive pay.

Weisselberg, who's due to testify next week, personally enjoyed some $1.76 million in rent-free apartments, luxury cars and other goodies over the years, but never mentioned it on W-2 forms.

On Monday, he will spend his fourth day on the witness stand, where he's been corroborating that he, Weisselberg, and other Trump executives, including the company's top lawyer and its COO.

Weisselberg, the trial's most important witness, was motivated by more than what one defense lawyer downplayed in opening statements.

There are three words that come in.

Bilge and thermometers

The defense wants the short phrase to swing the whole case in their favor.

"If the people fail to prove beyond a reasonable doubt that the acts were done in behalf of the Corporate Defendants but were instead for Weisselberg's benefit, then the jury must acquit the Corporate Defendants," Trump Organization lawyers argued.

The prosecutors tried to get the judge to strike the three words from the case entirely.

In defense of their love or hate of the three words, the sides have cited a variety of source material.

A federal appellate decision on a cargo ship that dumped 2,640 gallons of oily bilge off the coast of North Carolina is included in that.

The landmark prosecution was brought by the Brooklyn District Attorney who was an ardent Trump critic.

It was odd that the lawyers for Trump's business tried to use her case to their advantage.

She said that a case she brought to hold a company and its officers accountable was being used by a company that was trying to avoid being held accountable.

First of many battles

The first face-off over "in behalf of" came just days before jury selection began on October 24, as the sides sparred over what prospective jurors would be told about the trial.

"As evidenced by the papers you both submitted and research that we have been doing, it is far from clear what'means' you are talking about," the judge said at the October 20 pre- trial conference.

Alan Futerfas agreed that they were all wrestling with this.

The defense wanted the jury to be told that the Trump Organization can only be found guilty if Weisselberg and McConney broke the law in order to benefit the company.

Weisselberg and McConney would be the only witnesses who could show jurors their intentions.

Both men are still on Trump's payroll and their lawyers are paid by Trump's company. They are meeting with the defense to prepare their testimony.

They have to testify or face jail time. There was no mention of any intent to benefit Trump's company in Weisselberg's plea. The public record has shown that neither, so far as the records have shown.

It's no wonder prosecutors didn't try to benefit from the fact that Weisselberg was going to testify.

They wanted the judge to tell the jury that the company is guilty if its executives broke the law while doing their jobs.

The judge gave the parties more time to make a decision.

The parties went at it again at a second pre- trial conference. Joshua Steinglass, one of the lead prosecutors, pushed back against the idea that they had to prove intent.

The judge acknowledged that there was a lack of authority on the topic. I would love to write on it. I think it's fascinating.

He made an interim decision.

The judge said that much of the case law was not on point. He favors the plain and ordinary meaning of the phrase.

According to the website, "in behalf of" is defined as "in the interest of, or for the benefit of"

New York Criminal Law requires proof of conduct for the benefit of the corporation before a company can be found guilty, according to the judge.

The defense got what it wanted.

Both sides are expected to file lengthy motions, called "requests to charge," in the coming weeks, as they fight over what instructions the judge will give jurors when they step out of the deliberations room, weeks from now.

The district attorney's office and the attorneys for the Trump Organization did not respond. Weisselberg has continued to meet and prepare with both sides, according to Nicholas Gravante, a lawyer for Weisselberg.

He wants to take one more step towards having this unfortunate situation behind him by testifying.