OMAHA (AP) - A former Black Panther convicted nearly four decades ago in the bombing death of an Omaha police officer has filed another request to be released from prison.  Edward Poindexter, who's serving a life sentence at the state penitentiary, filed a petition for habeas corpus on Wednesday in U.S. District Court in Lincoln, saying he is being illegally held.  Habeas corpus is the right to seek relief from illegal detention.

Poindexter argues he's being illegally detained and that state officials are using laws created after his 1971 conviction and sentencing to keep him in prison.  Poindexter and a fellow Black Panther, David Rice, were convicted in Douglas County District Court for the death of officer Larry Minard.  Authorities say the pair lured police to a house with a 911 call in 1970, then detonated a homemade bomb that killed Minard. 

A spokeswoman for the state Department of Correctional Services referred questions to Attorney General Jon Bruning's Office. A spokeswoman in Bruning's office hadn't seen the filing and couldn't immediately comment on the case Thursday.

Last June, the state Supreme Court rejected a similar request in which Poindexter sought to overturn a district court's 2006 decision.

When he was sentenced, state law didn't require that sentences be commuted by the state Board of Pardons to be eligible for parole, he said.

Attorneys for the state argued that Nebraska law requires convicted offenders to serve half of their minimum sentences before becoming eligible for parole. Because it's impossible to calculate one-half of a life sentence, Poindexter's life sentence first must be commuted to a term of years before he can become eligible for parole, they said.  The state high court agreed.

In his federal habeas corpus case, Poindexter argues the state's parole board is using "unconstitutional tactics" to force a sentence on him of life without the possibility of parole.  He says he should have been released from prison in 1988.  "It is a fact that said parole board does not have any intention of ever seeing me released from prison," he wrote in court documents. "And given an opportunity, I can present a plethora of prima facie evidence to support all of my claims and allegations."

Poindexter also has another appeal pending with the Nebraska Supreme Court. In that case, he argued he wasn't given a fair trial, in part by allowing a jury to determine his guilt and sentencing in the same hearing.  The high court heard arguments in that case in October but hasn't issued a ruling.

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