Cop in NU grades case denies abuse claims

A retired police detective accused of abusing witnesses until they implicated an innocent man in a 1978 murder denies the claims in a videotaped interview with Northwestern University journalism students.

The interview was turned over to Cook County prosecutors this week.

Allegations that former Harvey Det. Coleman McCarthy coerced witnesses are central to students' claims that they uncovered evidence Anthony McKinney was wrongly convicted of murdering a security guard.

The Northwestern Center on Wrongful Convictions has submitted a petition on McKinney's behalf seeking a new trial that also includes claims McCarthy beat McKinney.

The case drew national attention when prosecutors subpoenaed the students' grades, private e-mails and Professor David Protess' syllabus.