FILE- In this Monday, May 31, 1999 file photo, Helen McHendry and husband Seamus find the agonizing wait for the recovery of Helen's mother all too much as Irish police continue to search for the body of her mother, Jean Mc Conville, in Dundalk, Irish Republic. Police in Northern Ireland arrested Sinn Fein party leader Gerry Adams on Wednesday over his alleged involvement in the Irish Republican Army's 1972 abduction, killing and secret burial of a Belfast widow. Adams, 65, confirmed his own arrest in a prepared statement and described it as a voluntary, prearranged interview. Police long had been expected to question Adams about the killing of Jean McConville, a 38-year-old mother of 10 whom the IRA killed with a single gunshot to the head as an alleged spy. According to all authoritative histories of the Sinn Fein-IRA movement, Adams served as an IRA commander for decades, but he has always denied holding any position in the outlawed group. (AP Photo/Peter Morrison, file) (The Associated Press)
Sinn Fein party leader Gerry Adams speaks to the media in West Belfast, Northern Ireland, Sunday May 4, 2014. Adams was released without charge Sunday after five days of police questioning over his alleged involvement in a decades-old Irish Republican Army killing, an event that has driven a dangerous wedge into Northern Ireland's unity government. (AP Photo/Peter Morrison) (The Associated Press)
A man passes graffiti on the Falls Road, West Belfast, Northern Ireland, Saturday, May, 3, 2014, in reference to former Republicans who took park in the Boston college tape recordings. Police continue to question the Sinn Fein leader Gerry Adams at Antrim police station about the 1972 murder of Jean McConville. (AP Photo/Peter Morrison) (The Associated Press)
"Free Adams" is seen written on a wall on the Falls Road, West Belfast, Northern Ireland, Saturday, May, 3, 2014. Police continue to question the Sinn Fein leader Gerry Adams at Antrim police station about the 1972 murder of Jean McConville. (AP Photo/Peter Morrison) (The Associated Press)
Author and IRA expert Ed Moloney talks to reporters at his home in New York, Thursday, May 1, 2014. Moloney, author of the definitive "A Secret History of the IRA," argues that the police investigation into Gerry Adams is designed not to bring justice but to claim the political scalp of Adams, who is Europe's longest-serving party leader. (AP Photo/Seth Wenig) (The Associated Press)
BELFAST, Northern Ireland – A police evidence file documenting Gerry Adams' Irish Republican Army career has been delivered to British state prosecutors in Belfast, but experts say the chances of the Sinn Fein leader being charged are slim on both legal and political grounds.
Adams walked free Sunday after five days of police interrogation and declared his innocence in the unsolved 1972 abduction, slaying and secret burial of a Belfast mother of 10, Jean McConville.
Adams says he chiefly was questioned about the audiotaped claims of IRA veterans, who identified him as the Belfast IRA commander at the time responsible for ordering McConville's disappearance.
Northern Ireland's Public Prosecution Service now must make the final call on whether police have collected enough evidence to charge the 65-year-old Adams with membership in an outlawed group.