By Tony Hanson

PHILADELPHIA (CBS) — A Philadelphia judge today convicted a man on drug charges even though an arresting officer in the case has admitted lying in another drug case in 2012, which was dismissed as a result.

Officer Christopher Hulmes was recently removed from street duty pending an investigation by the police department’s Internal Affairs unit.

The defense argued that Officer Hulmes’ testimony should be rejected in this case because of his earlier perjury admission.

But Hulmes testified in this case that he lied about the time of contact with an informant because he wanted to protect the informant from being hurt or killed.

After hearing all the evidence, including corroborating testimony from two other officers, Judge Francis Shields convicted the defendant of the purchase and possession of heroin.

Annie Fisher, a supervisor in the Public Defenders’ office, sees a problem with the conviction.

“When police officers admit to committing perjury and seem to have no fear that this district attorney’s office will prosecute them, it degrades the integrity of the entire criminal justice system,” she says.

The DA’s office says it will continue using Officer Hulmes’ testimony pending the outcome of the Internal Affairs investigation.

Defense attorneys have already challenged or are considering challenges of countless cases in which the veteran narcotics officer has testified. Defense lawyers in those cases contend that authorities should have disclosed — and were required by law to disclose — Hulmes’ prior perjury.