In a Virginia case, Edward B. MacMahon Jr., a lawyer for Ali al-Timimi, a Muslim scholar in Alexandria who is serving a life sentence for inciting his young followers to wage war against the United States overseas, said the government's explanation of how it came to suspect Mr. Timimi of terrorism ties never added up in his view.
F.B.I. agents were at Mr. Timimi's door days after the Sept. 11 attacks to question him about possible links to terrorism, Mr. MacMahon said, yet the government did not obtain a warrant through the foreign intelligence court to eavesdrop on his conversations until many months later.
Mr. MacMahon said he was so skeptical about the timing of the investigation that he questioned the Justice Department about whether some sort of unknown wiretap operation had been conducted on the scholar or his young followers, who were tied to what prosecutors described as a "Virginia jihad" cell.
"They told me there was no other surveillance," Mr. MacMahon said. "But the fact is that the case against a lot of these guys just came out of nowhere because they were really nobodies, and it makes you wonder whether they were being tapped."