Follow the money.

It’s the first lesson of white-collar prosecution 101 — yet there are serious questions whether David Weiss, the recently appointed “special prosecutor” in charge of the Hunter Biden corruption probe, performed that simple task.

If Weiss failed, it could be a greater crime than anything Don­ald Trump has done. In fact, white-collar attorneys tell me it suggests one of the biggest coverups since Watergate at the highest levels of the US government.

The most damaging stuff on Hunter’s laptop weren’t all those photos of Hunter doing drugs and hanging out naked with hookers.

Instead, it’s the paper trail of his manifold business entities that served as vehicles for his influence-peddling with shady foreign partners.

Hunter made a lot of money representing himself to these people as an expert in oil or whatever else he was touting.

As we all know, his real value was his last name and access to one of the most powerful people in the world, his dad, Sleepy Joe Biden.

It should be a prosecutor’s wet dream: The target, a ne’er-do-well son of a big-name politician, is running a string of suspicious, multimillion-dollar outfits and taking in bundles of cash from China, Ukraine, Russia and God knows where else.

The sordid mess caught the attention of the FBI after the target’s laptop was turned over to the feds.

Joe Biden, VP to Obama at the time, was investigating corruption in Ukraine, while Hunter was working with the Ukrainian oil company Burisma, itself investigated for bribery.

Emails from the target suggest he needs to pay off his old man, aka the “Big Guy,” when deals are done.

Banks, meanwhile, are always suspicious that money is being laundered and/or used in nefarious schemes.

In this case, the target’s activities left a paper trail miles long because he’s dealing in big bucks.

Transactions above $10,000, particularly those with overseas entities, are closely monitored by major banks under a variety of laws.

Suspicious deal

But the denouement to all of this is the following: A bizarre, cushy deal offered up by Weiss in which Hunter gets to plead guilty to failing to pay his taxes for two years, presumably when he was high on coke.

He’s also guilty on gun charges because what self-respecting cokehead with a hooker habit would be without an illegal firearm?

Suspicious? You’re not alone. For the record, I pretty much stayed out of the Hunter circus because I cover finance and banking.

But I was told last week by several of my sources that this is one huge banking story.

Maybe Weiss did the legwork with the banks and found nothing. But every high-level white-collar lawyer I spoke to — some of them former prosecutors — told me they doubt Weiss took even the basic steps in tracing the Hunter money trail because the end result was so lame. 

That means subpoenaing bank records, between the first son and the creeps across the globe, and since he’s at it, taking a look at the president’s bank records as well for kickbacks on possible influence peddling.

As one source told me: “Every bank in America knows where money is coming from and where it’s going. Based on what we’ve seen, it doesn’t look like Weiss subpoenaed Hunter or the president’s bank records. If the US Attorney who has been looking at this for years doesn’t know the sources of the money, that’s incredible because banks have that info handy.”

Why would Weiss lie down for the Bidens? Good question.

He was appointed as US Attorney for Delaware (the Bidens’ home state) by Trump. Then again, he now works for Joe Biden’s attorney general, Merrick Garland.

And the DC swamp makes for some strange bedfellows. Recall, the Trump-hating ex-FBI Director James Comey was once a Republican, and may still be as far as I know.

So, I lobbed a call into Weiss to inquire if he ever looked into the Biden money trail kept at the banks.

No answer.

Luckily, his crappy plea deal was recently nixed by a federal judge who also found it suspiciously lame.

Unluckily, Garland recently gave Weiss a second chance as a “special prosecutor” to look into stuff he presumably couldn’t or didn’t during his four-year probe.

Luckily again, the GOP took the House in the midterms, and an investigation by the Oversight Committee run by Rep. James Comer has turned up all sorts of interesting stuff, including Joe Biden’s seemingly more than casual relationship with Hunter’s suspect business.

According to testimony provided by Devon Archer, a former Hunter crony, Joe Biden appeared to have lied not knowing what Hunter did for a living; he was on calls with some of those foreign types from whom Hunter was seeking millions of dollars.

Maybe our brain-addled president simply forgot about all those calls. Either way, not a great look.

But who needs Sleepy Joe’s recollection of events when you have bank records? Comer plans to subpoena those as well, both Hunter’s and the president’s, he says.

We may finally find out what the Inspector Clouseau of the Justice Department missed — or chose to ignore.