A former Ann Arbor area bouncer who admitted he downloaded child pornography was sentenced Wednesday afternoon in federal court in Detroit to five years in prison.

Michael A. Robertson, 43, of Whitmore Lake, pleaded guilty March 10 to receiving child pornography, federal court records show. Robertson also worked as a piano instructor for children in the Whitmore Lake and Ann Arbor areas, a federal affidavit says.

Michael A. Robertson

U.S. District Judge David M. Lawson ordered that Robertson’s prison term be followed by five years of supervised release.

Immigration and Customs Enforcement agents were led to Robertson after German authorities launched a probe in July 2008 into a peer-to-peer file sharing network being used to trade child porn, records show.

Agents executed a search warrant on Aug. 4, 2009 at Robertson's home on Garfield Drive, seizing his computer and other items, records show.

Investigators recovered roughly 360 images and 73 videos of child pornography, according to an affidavit filed by ICE Special Agent Renaldo Franklin.

Some movies showed children "as young as 4 years old involved in sexual intercourse with other children and with adults," the affidavit says.

Robertson told investigators he viewed child porn about once a week, the affidavit says.

According to the affidavit, Robertson admitted to obtaining child porn over the Internet for "one to two years."

Brian Moskowitz, the special agent in charge of ICE Homeland Security Investigations in Detroit, said the agency is "dedicated to protecting our children and neighborhoods from sexual predators."

"We will continue to aggressively pursue and hold accountable individuals involved in this vile behavior," he said.

Lee Higgins covers crime and courts for AnnArbor.com. He can be reached by phone at (734) 623-2527 and e-mail at leehiggins@annarbor.com.