THE LATEST: Brendan Dassey takes appeal to federal court

MILWAUKEE (AP) — The man convicted of helping his uncle kill Teresa Halbach in Manitowoc County is taking his legal challenge to federal court.

Lawyers for Brendan Dassey recently filed a petition in federal court asking a judge to decide whether his arrest and conviction were legal.

Dassey was 16 when Halbach was killed in 2005 after she went to the Avery family auto salvage yard to photograph some vehicles. Dassey's uncle, Steven Avery, was tried and convicted separately in the homicide.

The Wisconsin Supreme Court last year declined to take Dassey's case. Post-Crescent Media reports the federal case, like his appeals in state court, argue Dassey's constitutional rights were violated because of ineffective counsel and an involuntary confession.