Gov. Andrew Cuomo’s press office is busy downplaying the governor’s controversial 90-day email purge policy, saying the practice has been in place in the executive chamber – albeit not enforced across executive agencies – since 2007.

In other words, since before Cuomo took office in January 2011.

That would mean this policy was established under former Gov. Eliot Spitzer, who was elected in 2006 and knew a little something about the power of an email trail from his days in the AG’s office.

And speaking of the AG’s office, it turns out the executive branch isn’t the place where the 90-day purge policy exists.

The NYS Department of Law, currently headed by AG Eric Schneiderman, adopted that selfsame policy way back in 2007 – in other words, the year Cuomo succeeded Spitzer in the AG’s office.

An AG office source confirmed Schneiderman opted to keep the email deletion policy put in place by Cuomo. According to this source, the office maintains “any emails that may be relevant to litigation – including the discovery process of a potential or ongoing case.”

Asked how the AG’s office determines which emails, exactly, are going to be pertinent in yet-unknown future lawsuits, and what is kept, the source replied:

Anything that could constitute as evidence in the discovery process – emails from clients regarding a case, minutes of meetings, documents that initiative or complete a business transaction, final reports. It’s not an automatic ‘hold’ per se, but the lawyers follow this closely – otherwise their investigations and cases would be hampered.

Meanwhile, the state comptroller’s office is also reviewing Cuomo’s 90-day purge policy with an eye toward determining if any of its functions – namely, investigations and audits – will be negatively impacted.

State Comptroller Tom DiNapoli’s spokeswoman Jennifer Freeman noted that email trails are often used by investigators to catch government officials engaged in wrongdoing, and if those trails are no longer available, it could curtail corruption-busting probes.

DiNapoli’s office does not have an email purge policy, and has “no intention” of following Cuomo’s policy, Freeman said.

Any email deleted by a staffer in the comptroller’s office is backed up for two weeks, and all executive and senior staff members have been afforded “extensive” amounts of storage space to avoid having to delete anything that might be of value sometime down the road.

“There’s no way storage is an issue,” Freeman said. “It’s cheap.”

Freeman said DiNapoli has both private and state-issued emails accounts, and sometimes uses the former for public business. When the comptroller first took office, he was issued a public account and was “blasted” with emails, Freeman explained. As a result, multiple email accounts were established for the comptroller, with some of his work emails monitored by his assistants.