The incident he referred to was from the Obama era and wasn't spying. From the Times:
"WASHINGTON — John H. Durham, the Trump-era special counsel scrutinizing the investigation into Russia’s 2016 election interference, distanced himself on Thursday from false reports by right-wing news outlets that a motion he recently filed said Hillary Clinton’s campaign had paid to spy on Trump White House servers.

Citing a barrage of such reports on Fox News and elsewhere based on the prosecutor’s Feb. 11 filing, defense lawyers for a Democratic-linked cybersecurity lawyer, Michael Sussmann, have accused the special counsel of including unnecessary and misleading information in filings “plainly intended to politicize this case, inflame media coverage and taint the jury pool.”

In a filing on Thursday, Mr. Durham defended himself, saying those accusations about his intentions were “simply not true.” He said he had “valid and straightforward reasons” for including the information in the Feb. 11 filing that set off the firestorm, while disavowing responsibility for how certain news outlets had interpreted and portrayed it.

“If third parties or members of the media have overstated, understated or otherwise misinterpreted facts contained in the government’s motion, that does not in any way undermine the valid reasons for the government’s inclusion of this information,” he wrote."
There's more if you want to read it in the Times.
Stupid righties.