Michigan State Police are reviewing the process used to determine when to refer a case to prosecutors for criminal review and have launched an investigation into how employees treated a drunken driver after his December 2017 arrest.

The action follows a Free Press investigation that examined the violent arrest of Jason Spicer in Royal Oak.

A State Police statement said the agency's initial review of the incident missed "unprofessional and derogatory comments" made by employees. The comments were included in the Free Press report.

Troopers transported Spicer, a disabled motorist who walks with a cane, to State Police’s Metro North Post in Oak Park after his drunken driving arrest.

As Spicer was being escorted from the post about 3:30 a.m., an unidentified male voice can be heard on video saying: “Come back and see us, ya little bitch.”

It’s not clear whether Spicer was within hearing range. Laughter followed the remark, then a mocking impersonation of Spicer, who had complained repeatedly that he was numb.

"Now that we are aware of these comments and the conduct of our employees after Mr. Spicer’s arrest, an internal investigation has been opened into the treatment of Mr. Spicer while he was being held at the Metro North Post," State Police spokeswoman Shanon Banner said in an email. "The Michigan State Police holds its members to the highest standards of professional conduct and we expect our employees to treat everyone with dignity and respect."

The investigation will attempt to determine who made those comments, she said.

"After seeing the Free Press’ report ... the MSP undertook an internal review of the recording to try to determine why the internal affairs report indicated there was no audio available from the recordings taken at the post," Banner said.

Officials have now determined there was a software issue with the computers used by internal affairs and the audio could not be played on their computers, she said. The department is upgrading its computers to prevent audio issues in the future.

A focus of the Free Press investigation was how the department handled Spicer's case, which is cited as part of a lawsuit filed by the former head of internal affairs.

Gov. Gretchen Whitmer weighed in after the Free Press report and video published earlier this month, saying she was concerned and planned to seek more information. The arrest happened before she was governor.

Read more:

More:Violent traffic stop cited in ex-MSP official's lawsuit. We have the video.

More:Gov. Gretchen Whitmer responds to Freep investigation into Michigan State Police

Now-retired 1st Lt. Twana Powell, the head of internal affairs at the time of the arrest, says in her suit she wanted prosecutors to review it for unlawful excessive force. A high-level supervisor denied her request, she says.

Officials haven't explained why State Police did not seek that review.

In March 2018, State Police finished the internal affairs investigation into the incident and the conduct of troopers involved.

“While we do stand by the completeness of our investigation and do not plan to re-investigate this incident, we are using this experience as an opportunity to review our official orders to provide further clarity regarding the process that is used to determine whether an incident merits criminal review by a prosecutor,” Banner said.

Dash cam video of the Dec. 28, 2017, traffic stop shows Trooper Mark Carroll yank a cane from Spicer's vehicle. Then Carroll pulls Spicer out and slams him to the ground. It appears Spicer’s head smacks the pavement during the takedown. Later, after he was handcuffed, Spicer's blood pooled on the hood of patrol car.

In the video, Carroll also appears to kick Spicer’s legs apart while Spicer is handcuffed. Spicer repeatedly told troopers that night he suffers from nerve damage.

Carroll wrote in a police report that Spicer had refused repeated orders to get out of the SUV, grabbed a cane and started to come toward him with it.

Carroll recounted the arrest at the post about 30 minutes after it happened and can be heard on video acknowledging that Spicer had told him he was going to get out of his vehicle and that he has trouble walking.

"He gets a cane and starts swinging," Carroll tells his coworkers. "I just grabbed it right from the vehicle, ripped it right out."

Two of Carroll's supervisors watched video shortly after the arrest and expressed concerns about the level of force. The case was referred to internal affairs.

Powell found the trooper’s conduct “discriminatory and potentially criminal,” her lawsuit says. The motorist is black and the trooper is white, the suit says.

Powell alleges that MSP suffers from "a pattern of discrimination against both citizens and agency employees." State Police have denied that claim.

The lawsuit is scheduled for trial next year in Ingham County Circuit Court.

Last year, Spicer, 42, pleaded guilty to a second offense of operating while intoxicated, court records show.

Troopers had pulled him over on I-696, near Woodward Avenue, just after 2 a.m.

Spicer was traveling at 90 mph and weaving, according to a police report.

He had a blood alcohol content of .22 — nearly three times the legal driving limit.

Contact Elisha Anderson: eanderson@freepress.com or 313-222-5144.