WASHINGTON — Prosecutors like to say that they investigate crimes, not people. The looming decision by the Manhattan district attorney about whether to indict former President Donald J. Trump on charges related to an alleged hush money payment to a porn actress is highlighting the complexity of the legal calculations being made by prosecutors in New York, Georgia and the Justice Department as they examine Mr. Trump’s conduct on a number of fronts.

The investigations — which also focus on Mr. Trump’s efforts to cling to power after the 2020 election and his handling of classified documents after leaving office — are confronting prosecutors with tough choices. They must decide whether and how to charge not just Mr. Trump, but also associates who could face jeopardy for actions to which he was not a direct party, like mail or wire fraud for communications that he did not participate in.

The publicly known understanding of the evidence is incomplete. It is not clear, for example, in several instances what facts investigators have been able to gather about Mr. Trump’s personal knowledge, directions and intentions related to several of the matters.

Here is a look at some of the criminal laws that different prosecutors appear to be weighing and how they might apply to Mr. Trump’s actions.

The Stormy Daniels Hush Money Payment

Overview

Alvin L. Bragg, the Manhattan district attorney, appears to be nearing a decision about whether to charge Mr. Trump with a crime related to his $130,000 hush money payment just before the 2016 election to the pornographic film actress Stormy Daniels, who has said they had an extramarital affair. Michael D. Cohen, Mr. Trump’s former lawyer and fixer, sent the money to Ms. Daniels, and the Trump Organization reimbursed him over the course of 2017, according to a 2018 federal court filing in Mr. Cohen’s case. Mr. Trump’s business concealed the true purpose of the payments, the filing said, by recording them as having been for a legal retainer that did not exist.

Potential charge: Bookkeeping fraud

The New York Times has reported that the case may include a potential charge of falsifying business records under Article 175 of the New York Penal Law. A conviction for a felony version of bookkeeping fraud carries a sentence of up to four years.

To prove that Mr. Trump committed that offense, prosecutors would seemingly need evidence showing that he had knowingly caused subordinates to make a false entry in his company’s records “with intent to defraud.” For the action to be a felony rather than a misdemeanor, prosecutors would also need to show that Mr. Trump falsified the business records with the intention of committing, aiding or concealing a second crime.

The public understanding of Mr. Bragg’s theory of the case remains murky and incomplete. The district attorney’s office has reportedly weighed invoking alleged campaign-finance violations as that intended second crime, which could raise complications. Among other things, presidential elections are governed by federal law, and it is not clear whether Mr. Bragg has found a theory by which a state campaign law covered Mr. Trump’s actions, or if a state prosecutor can cite a law over which he lacks jurisdiction. It remains possible that Mr. Bragg has obtained nonpublic evidence of some other intended offense, like if there was any initial intention to deduct the payments as a business expense on state tax returns.

Bookkeeping fraud has a two-year statute of limitations as a misdemeanor and a five-year one as a felony, both of which would normally have expired for payments made to Mr. Cohen in 2017. But New York law extends those limits to cover periods when a defendant was continuously out of state, as Mr. Trump was while living in the White House or at his home in Florida. In addition, during the pandemic, New York’s statute of limitations was extended by more than a year.

The Mar-a-Lago Documents

Overview

Jack Smith, a special counsel for the federal Justice Department, is investigating matters related to Mr. Trump’s handling of several hundred documents marked as classified that he kept at his Florida club and home, Mar-a-Lago, after leaving office, and how Mr. Trump resisted efforts by the government to retrieve all of those files. After the Justice Department obtained a subpoena for all remaining files marked as classified, a lawyer for Mr. Trump, M. Evan Corcoran, turned over some while helping to draft a statement falsely saying those were all that remained. In August, the F.B.I. executed a search warrant and found 103 more, including in Mr. Trump’s desk.

Prosecutors last week persuaded a federal judge that Mr. Corcoran should be compelled to answer more questions from a grand jury investigating the documents matter, notwithstanding attorney-client privilege. That means the judge agreed with prosecutors that the situation met the threshold for an exception for lawyer communications or work that apparently helped further a crime.

Potential charge: Unauthorized retention of national security documents

One of the charges the F.B.I. listed in its affidavit for the Mar-a-Lago search warrant was Section 793(e) of Title 18, a provision of the Espionage Act. Prosecutors would have to show that Mr. Trump knew he was still in possession of the documents after leaving the White House and failed to comply when the government asked him to return them and then subpoenaed him. The theoretical penalty is up to 10 years per such document.

Prosecutors would also have to show that the documents related to the national defense, that they were closely held and that their disclosure could harm the United States or aid a foreign adversary. Although Mr. Trump has claimed — without evidence — that he declassified all the files taken to Mar-a-Lago, prosecutors would not need to prove that they were still classified because the Espionage Act predates the classification system and does not refer to it as an element.

Potential charge: Obstruction

Another charge in the F.B.I. affidavit was Section 1519 of Title 18, which makes it a crime to conceal records to obstruct an official effort. Prosecutors would need to show that Mr. Trump knew he still had files that were responsive to the National Archives’ efforts to take custody of presidential records and the Justice Department’s subpoena for files marked as classified, and that he intentionally caused his subordinates to fail to turn them all over while leading officials to believe they had complied. The penalty is up to 20 years per offense.

Potential charge: Mishandling official documents

A third charge in the affidavit was Section 2071 of Title 18, which criminalizes the concealment or destruction of official documents, whether or not they were related to national security. Among other things, former aides to Mr. Trump have recounted how he sometimes ripped up official documents, and the National Archives has said that some of the Trump White House paper records transferred to it had been torn up — some of which were taped back together and some of which were not reconstructed. The penalty is up to three years per offense plus a ban on holding federal office, although the latter is most likely unconstitutional, legal experts say.

Potential charge: Contempt of court

Section 402 of Title 18 makes it a crime to willfully disobey a court order, like the grand jury subpoena Mr. Trump received in May 2022 requiring him to turn over all documents with classification markings remaining in his possession. It carries a penalty of a fine of up to $1,000 and up to six months in prison. To bring this charge, prosecutors would need evidence showing he knew that he was still holding onto other files with classification markings during and after his representatives purported to comply with the subpoena.

Potential charge: Conspiracy to make a false statement

Section 1001 of Title 18 makes it a crime to make a false statement to a law enforcement officer about a fact material to the officer’s investigation, and Section 371 makes it a crime to conspire with another person to break that or any other law. It carries a penalty of up to five years. Prosecutors would need to be able to show that Mr. Trump and Mr. Corcoran knew and agreed that the lawyer should lie to the Justice Department about there being no further documents responsive to the subpoena.

The Georgia Election Law Investigation

Overview

Fani T. Willis, the district attorney for Fulton County, Ga., is investigating events related to Mr. Trump’s attempts to overturn President Biden’s narrow victory in that state in the 2020 election. Among other things, in a phone call that was recorded and leaked, Mr. Trump called Georgia’s secretary of state, Brad Raffensperger, and pressured him to “find” enough additional votes for him to flip the outcome.

Ms. Willis is also investigating Trump associates’ efforts to get 16 of his supporters to falsely declare themselves to be an alternative slate of electors from Georgia, which helped lay the groundwork for Mr. Trump’s push to get Vice President Mike Pence to reject the true results when Congress met to certify the election on Jan. 6, 2021.

Potential charges: Election code violations

Most elections offenses in Georgia’s code are misdemeanors, but there are several felony charges that Ms. Willis may be considering, based on the same basic set of facts. These include Section 21-2-603, which makes it a crime to conspire with another person to violate a provision of the election code, and Section 21-2-604, which makes it a crime to solicit another person to commit election fraud.

To bring such a charge against Mr. Trump, prosecutors would need to cite another election law whose violation was his alleged goal. It is possible, for example, that they might be considering contending that Mr. Trump’s pushing Mr. Raffensperger to “find” additional votes amounted to implicitly asking him to violate a provision that makes it a felony for the secretary of state to alter official election records, but Mr. Trump’s language was not explicit.

Potential charge: Racketeering

Ms. Willis has indicated that she is considering bringing charges under Georgia’s Racketeer Influenced and Corrupt Organizations Act. So-called RICO laws are tools that were developed to make it easier to go after organized criminal enterprises, and can be used against members of any group that engaged in a pattern of criminal activities with a common purpose. A conviction would carry a maximum penalty of 20 years in prison.

To convict Mr. Trump under Georgia’s RICO law, Section 16-14-4, prosecutors would need to show that as part of his efforts with associates to overturn Georgia’s election results, he conspired with others or engaged in two or more offenses from a list of several dozen offenses, most of which are violent crimes but which include things like solicitation, forgery and making materially false statements to state officials.

The 2020 Election and Jan. 6

Overview

Mr. Smith, the special counsel, is also conducting a broader federal investigation into Mr. Trump’s attempt to overturn the 2020 election results and the events of Jan. 6. The House committee that carried out the investigation into the riot last year made a criminal referral of Mr. Trump and others to the Justice Department. While that was of largely symbolic value — the department already had an investigation open and Congress has no authority to prosecute — the analysis in the panel’s final report sets out possible charges that Mr. Smith could also consider.

Potential charge: Obstruction of an official proceeding

One criminal accusation the Jan. 6 committee leveled against Mr. Trump was the attempted corrupt obstruction of an official proceeding, under Section 1512(c) of Title 18. It is punishable by up to 20 years in prison. Prosecutors have used this law to charge about 300 ordinary Jan. 6 defendants — people who rioted — and an appeals court is currently weighing whether that charge has been appropriately applied in those cases. But even if the judiciary upholds use of the charge, such a case against Mr. Trump would be very different since he did not physically participate in the riot.

The Jan. 6 committee argued that he could be charged with it based on two sets of actions. First, it argued that his summoning of supporters to Washington and urging them to march on the Capitol and “fight like hell” violated that law. Mr. Trump’s defense team would surely seek to raise doubt about whether he intended for his supporters to riot, including because he also told them to protest “peacefully.”

Second, the committee portrayed as criminal obstruction the scheme to recruit so-called fake electors from various states and pressuring Mr. Pence to cite their existence as a basis to delay certifying the election. The panel stressed how Mr. Trump had been told that there was no truth to his claims of a stolen election, which it said proved his intentions were corrupt. Among other things, Mr. Trump’s defense team would surely argue that because a lawyer, John Eastman, advised him to take those steps, there is no proof he understood that doing so was illegal.

Potential charge: Conspiracy to defraud the United States

A second criminal accusation leveled by the Jan. 6 committee was Section 371 of Title 18, which makes it a crime, punishable by up to five years in prison, to conspire with another person to defraud the government. The panel cited an array of evidence about Mr. Trump’s interactions with various lawyers and aides in pursuit of his effort to prevent the certification of Mr. Biden’s electoral victory. The committee also argued that prosecutors could prove Mr. Trump intended to be deceitful via evidence that he was repeatedly told that his allegations of widespread voter fraud were baseless.

Potential charge: Conspiracy to make a false statement

The Jan. 6 committee highlighted the efforts to submit slates of fake electors to Congress and to the National Archives. As with other such potential charges, a key challenge for prosecutors would be proving Mr. Trump’s intentions and understanding beyond a reasonable doubt.

Potential charge: Insurrection

The committee also pointed to Section 2383 of Title 18, which makes it a crime to incite, assist or “aid and comfort” an insurrection against the authority and laws of the federal government. The panel emphasized in particular how Mr. Trump refused for hours to take steps to call off the rioters despite being implored by aides to do so, and an inflammatory tweet he sent about Mr. Pence in the midst of the violence.

While the committee said the events of Jan. 6 met the standard for an insurrection, it is notable that prosecutors have not accused any of the Jan. 6 defendants to date of that offense — even those they charged with seditious conspiracy.