A Silver Spring man whom Montgomery County police and prosecutors believe was behind a string of burglaries and thefts in 2011 was found guilty Monday in the second trial centered on the thefts.

Last Thursday, Michael B. Dorsey of Silver Spring also was convicted in the first trial.

He faces three more trials this week.

Montgomery County Assistant State’s Attorney Steve Chaikin said the prosecution originally planned to try Dorsey in one trial, but decided to hold separate trials after the defense filed a motion to sever the trial into individual trials.

Dorsey was convicted Monday on a count of theft and one count of roving vagabond, which is being in a car with the intent to steal property from inside the vehicle.

Dorsey was convicted on Feb. 7 of one count each of theft and misappropriation of a credit card and two counts of identity fraud in Montgomery County Circuit Court before Judge Sharon V. Burrell.

So far, the convictions in the two trials could mean up to 10 1/2 years in prison when Dorsey is sentenced.

His sentencing in the first case is set for April 10. He could receive up to 72 months in prison, Chaikin said.

The charges in the second trial came after Dorsey was caught in a web of visual surveillance by different undercover officers as he carried out the thefts in the parking lot of a plastic surgery facility on Old Georgetown Road in Bethesda, according to Chaikin.

Dorsey is representing himself in the trials.

“The advancement of technology and good old-fashioned police work solved this case,” Chaikin told the jury in his opening arguments of the first trial, adding that the case was “really a connect-the-dots case, but really a very strong case.”

In that first case, Dorsey was accused of using a credit card stolen out of a car in Potomac to buy an American Express gift card. He also has been charged with smashing the windows of cars around the county to steal property inside, charging documents said.

Dorsey argued that the evidence offered by the state lacked credibility, and could have been forged or fabricated.

Much of his defense centered on the timing of the video footage used in the trial. “Timing is everything,” he told the jury.

He tried to cast doubt on the legitimacy of the footage, because the times in the video did not match up with the times when the stolen credit cards were used.

Witnesses said time differences are not unusual and can occur when the video cameras are on separate computer systems than the ones which host the credit card swipers.

Before he was convicted, Dorsey asked the judge to acquit him on the grounds that the evidence presented was insufficient.

“I think that’s exculpatory,” he said.

sjbsmith@gazette.net