A man prosecutors say was one of the nation's most prolific child molesters was convicted Monday of abusing two 12-year-old boys.

The jury deliberated for just four hours before finding Dean Schwartzmiller, 64, guilty of 11 felony counts of child molestation and one misdemeanor charge of child pornography possession.

Click here to visit FOXNews.com's Crime Center

Schwartzmiller, who represented himself during the trial but asked for an attorney to represent him during the sentencing phase, stood with his arms crossed as the verdicts were read. He faces up to life in prison.

Prosecutor Steve Fein said outside court that Schwartzmiller subjected jurors to unneccessary videotaped testimony and diatribes about how society doesn't accept pedophiles.

"A lawyer typically knows what the rules are. He had his own agenda," Fein said.

Prosecutors said Schwartzmiller, who has at least three other molestation convictions and a dozen arrests over three decades, left a trail of abused children.

During the nearly three-week trial, prosecutor Steve Fein showed jurors a map of the "places and decades where the defendant has molested young boys." It included an estimated 100 accusers dating to 1969 in eight U.S. states, Mexico and Brazil.

Prosecutors pointed to a graphic 456-page memoir, 10 binders full of child pornography and 1,500 notebook pages with headings including "no, but yes boys," "best of the best, 13 and under" and "single-parent boys."

Schwartzmiller said the memoir and notebook entries were fiction. He blamed his roommate, Frederick Everts — also a convicted child molester — for the child porn.

Schwartzmiller testified on his own behalf and said he could not have molested the two boys, who are cousins, because he was either at a construction job or bedridden with a bad back at the time. In his closing argument, he noted discrepancies in testimony by the boys.