Since John Roberts became chief justice in 2005, the US Supreme Court has been doing all it can to legalise corruption.

“No quid pro quo” is a magic phrase. A lot like “no collusion”.

It is also the tip of an iceberg. An extremely dangerous one: the legalisation of corruption.

The phrase popped up after William Taylor, the top US diplomat in Ukraine, wrote to Gordon Sondland, the US ambassador to the EU, “I think it’s crazy to withhold security assistance for help with a political campaign.”

Sondland responded: “The President has been crystal clear no quid pro quo’s of any kind.” He then went on to suggest they stop “the back and forth by text,” adding that if Taylor still had concerns, he could “talk” to others.

“Quid pro quo” is very simple. It translates – and actually means – “this for that”. It might appear that Sondland is denying that such a deal is taking place. That’s not what he’s saying. Not at all.

He’s saying that Trump is saying “no quid pro quo’s,” therefore, William, you better not say there is one or you better stop describing stuff that sounds exactly like “quid pro quo’s” and if it bothers you so much that you cannot stop, do not do it in writing, there are a couple of people you can call about it.

The reason that particular phrase is so important is that the Supreme Court has made it so.

John Roberts became chief justice in 2005. Since then, the Supreme Court has been on a campaign to legalise, normalise and, ultimately, enshrine political corruption. That sounds like it must be an exaggeration. It is not.

The common understanding of corruption is that if Public Office Holder gets money, vacations, Rolexes, other gifts and fancy things from “a person with a lot of money”, and then does things that benefit that person, particularly if they do not benefit or they harm the public interest, that is corruption.

As more and more money poured into political campaigns, it became obvious that large sums had a corrupting effect and, worse, that they were distorting the entire political process. Even politicians thought so and attempted to restrain spending with laws such as McCain-Feingold (named after the late Republican Senator John McCain, and Russ Feingold, a Democrat).

Once Roberts took charge with a Republican majority on the Supreme Court, they began to invent ways to rule in favour of money and strike down any laws that diminished its power. First, they defined spending money on speech as speech, and therefore protected by the First Amendment.

In Citizens United vs Federal Election Commission, the majority opinion literally redefined reality: “Independent expenditures, including those made by corporations, do not give rise to corruption or the appearance of corruption.”

Having redefined reality, they said doing so would have no effect: “The appearance of influence or access will not cause the electorate to lose faith in this democracy.”

Justice Anthony Kennedy, in the majority opinion, quoted himself from another case (McConnell vs Federal Election Commission) writing: “It is well understood that a substantial and legitimate reason, if not the only reason, to cast a vote for, or to make a contribution to, one candidate over another is that the candidate will respond by producing those political outcomes the supporter favors. Democracy is premised on responsiveness.”

It is an astonishing statement. It says people are supposed to spend money to get politicians to do what they want, and that politicians are supposed to “respond” to getting money.

The court was not going to say flat out, “there’s no such thing as corruption any more.” They had to leave something. Along the way, it decided to settle on “quid pro quo” as the standard.

“Any [campaign finance] regulation must instead target what we have called ‘quid pro quo’ corruption or its appearance. That Latin phrase captures the notion of a direct exchange of an official act for money.”

There was a class element to this. Nobody ever suggested that Dick Cheney should be prosecuted because he gave the contract to privatise the US military to Halliburton and, after he left office, Halliburton made him a very rich man as their CEO.

Such things, on a smaller scale, had become standard practice with government contracting, especially military contracting. But unless there was a written or audio record of the deal being made, as a “quid pro quo”, there could not even be a presumption of corruption, let along prosecutions.

In 2016, the Roberts Court made it even worse. Bob McDonnell, as governor of Virginia, had taken $175,000 from a businessman and then done him favours.

A jury convicted McDonnell. John Roberts set him free, declaring “conscientious public officials arrange meetings for constituents, contact other officials on their behalf, and include them in events all the time. The basic compact underlying representative government assumes that public officials will hear from their constituents and act appropriately on their concerns …”

Several significant corruption cases were either stopped or tossed immediately after that decision.

It appears that Sondland will testify that he was not speaking of his own assessment. That he had been directed by Donald Trump to say the magic words. You can see why Trump would believe that simply uttering the incantation, “no quid pro quo”, would decriminalise his crime.

Even if Trump is held liable, the greater underlying problem remains.

Corruption is a significant factor in the great malaise of today’s world. The “feeling” that the elites were institutionally corrupt created the opportunity for Trump to be elected.

The reality that corruption has been more and more normalised, has allowed Trump to turn the presidency into an office dedicated to personal profiteering.

The rich like being able to call on government, shape government, use government – that is, they like institutional corruption, a lot – and will not give it up easily. That is the big fight.

The views expressed in this article are the author’s own and do not necessarily reflect Al Jazeera’s editorial stance.