Twenty years after he broke into two South End apartments and raped the occupants, a serial rapist was sentenced to 20 years in state prison, with that term to follow the 40-year term he’s already serving for breaking into another home and brutalizing two elderly women.

Suffolk County District Attorney Daniel F. Conley’s office recommended life in prison for MICHAEL JOHNSON (D.O.B. 4/9/69) following his conviction yesterday for the April 10, 1990, aggravated rape of a 23-year-old woman on Wellington Street. Prosecutors recommended an additional 20-year prison term for the May 7, 1990, rape of a 24-year-old woman on West Concord Street and another 20-year prison term for the attempted rape of that woman’s 30-year-old roommate.

Prosecutors had further asked that the sentences run consecutive from one another for a total of life in prison plus forty years, to begin only after his current prison terms end.

Superior Court Judge Peter Lauriat sentenced Johnson to terms of 17 to 20 years in prison on the April 1990 rape and a concurrent 10 to 15 years on the May 1990 rape, with seven years probation upon his release. Lauriat ordered that the sentence begin after Johnson completes the 33- to 40-year term he is serving following his 2003 conviction for a violent 1999 home invasion.

During two weeks of trial, Assistant District Attorney Leora Joseph and Barbara Young of Conley’s Family Protection and Sexual Assault Bureau proved that Johnson gained entry into the two residences and brutally raped the occupants. He covered the first victim’s face with a towel and attacked the second set of victims in the dark. None of the victims could identify him.

A break came in 2003, when Boston Police and Suffolk prosecutors reviewed those attacks while undertaking a project to examine cold cases with newly-admissible DNA evidence. When the biological evidence recovered from the victims’ rape kits was uploaded to CODIS – the nationwide Combined DNA Index System – they matched each other and Johnson’s DNA profile, which had previously been submitted as part of his home invasion prosecution.

Further investigation led to Johnson’s 2005 indictment on the rape charges; prosecutors could not pursue breaking and entering, kidnapping, or related charges because the statute of limitations had by that time expired.

Prior to sentencing, Joseph read statements from two of the victims.

“I found it very difficult to feel safe in nearly every environment including my own home, neighborhood, and workplace,” the first victim wrote. “I believe it is important for the court to understand that this crime rocked my faith in humanity. It was such a personal violation …. I fully support a life sentence for [the defendant]. I believe that he is such a high-risk danger to the public that he should never be considered for release under any condition.”

The woman Johnson raped in May 1990 wrote that she suffered a facial injury during the attack that she sees in the mirror every day.

“A small indentation on my forehead is an ever-present reminder of the incident,” she wrote. “Almost every time I look in a bathroom mirror, I think: I was raped …. I ask for the maximum sentence, not served concurrently with any other sentences. Having helped convict my rapist, I would never feel comfortable knowing he was free until the court is satisfied that he has served his punishment, is rehabilitated, and presents no danger to anyone.”

The woman Johnson tried to rape in the early morning hours of May 7, 1990, and who struck him with an iron fireplace poker, prompting him to flee, traveled to Boston to address the court directly. She took to the podium and spoke two sentences in a steady voice.

“He attacked me violently,” she said. “If things had gone the way he said he intended them to, this would have been a murder trial.”