Federal and local law enforcement authorities are investigating a shooting in Prince George's County that critically injured a prominent intelligence expert who specializes in the former Soviet Union. Paul Joyal, 53, was shot Thursday, four days after he alleged in a television broadcast that the government of Russian President Vladimir Putin was involved in the fatal poisoning of a former KGB agent in London... Joyal was shot by two men in the driveway of his house in the 2300 block of Lackawanna Street in Adelphi about 7:30 p.m. Thursday... The identity of the shooters was unknown, and Prince George's police...