Richard Patterson, 46, and his wife Christina are said to have been caught on film with the dog in their master bedroom.
The “sexual activity” footage was reportedly found on a video after a raid by officers searching for illegal guns at their home.
Detectives are now probing “crimes against nature” in Suffolk, Virginia.
State law forbids someone from “carnally knowing in any manner any brute animal,” or submitting to such acts.
Convictions can lead to a year in jail and a $2,500 fine.
Neither of the Pattersons, who also train police dogs, has yet been charged over the alleged bestiality, which is still under investigation, according to city spokeswoman Diana Klink.

A Doberman called Demon, [photo], was the alleged victim

The Doberman-involved sex tape was discovered in the couple’s home by an Alcohol, Tobacco, Firearms and Explosives agent after a computer was taken from the couple’s house, say court files.
Richard Patterson’s lawyer Andrew Sacks said he would not confirm nor deny the information in the search warrants.
But he spoke out about the investigation.
He said: “Number one, we believe that what two consenting adults do in private, in their bedroom is off limits.
“Number two, we don’t believe there was a valid law in place that even affected this at the time.
“And number three we seriously question the police reaching out into this type of material when it has nothing to do with what they were searching for to begin with.”

The Pattersons run Imperial Kennels and K-9 Training Services, [photo]

Christina Patterson’s lawyer Nicholas Renninger said: “Mrs Patterson is ready to defend herself in court if necessary.
“But at this stage, she has not been indicted or charged with any crime.”
The Pattersons’ Imperial Kennels and K-9 Training Services offers a facility for all breeds of dogs, according to an online site.
It says: “We specialise in behavioural problems, obedience training, and offer protection training for Police, military, and average citizens.
“We also offer full service boarding facilities, and are AKC inspected and State licensed.”

Imperial Kennels and K-9 Training Services, [photo], breeds thorough bred canines. trains dogs as well, specializes in dogs with behavioral problems in the Norfolk, Virginia area

Richard Patterson has been indicted in Norfolk Federal District Court for allegedly having 17 firearms as a convicted criminal.
The weapons, including handguns, shotguns and military-style rifles, were reportedly shipped over state lines.
He also had 52 shotgun shells, 44 rounds of .40-caliber bullets and 10 rounds of .357 ammunition, said prosecutor William Jackson.
Patterson previously convicted of three crimes – forging public records, perjury in DMV matters and larceny – in June, it has been reported.
He was sentenced to six years in prison, but a judge suspended all of it.