The FBI has tried to bolster its case for expanded Internet surveillance powers by gathering finger-pointing examples of how communications companies have stymied government agencies, CNET has learned.

An internal Homeland Security report shows that a working group convened by an FBI office in Chantilly, Va. requested details about "investigations have been negatively impacted" by companies' delays, partial compliance, or inability to comply with police surveillance requests.

One of the claims in that report: A police arm of Homeland Security's Immigration and Customs Enforcement, which conducts investigations into immigration, drug, computer, and copyright crimes, reported that no-contract wireless provider Cricket Communications had "hindered" an investigation because "system technical issues" interfered with a wiretap and location tracking. Cricket, a subsidiary of Leap Wireless, has approximately 6 million subscribers.

The "noncompliance incident report" says that:

On almost a daily basis, we experienced technical issues with our target line serviced by Cricket Communications. These problems included daily occurrences of intercepted communications that were missing either data or content. We had numerous instances of calls received where direction and/or digits were not provided by the service provider. Also, for approximately four months the office attempted to obtain a usable cellsite mapping template for target location data. Several Cricket employees were notified of the problem multiple times over a four month time period. No satisfactory resolution was ever provided by Cricket.

Greg Lund, a spokesman for Cricket, told CNET today that "we review all incoming legal requests to determine what information is requested and whether disclosure of that information is lawfully permitted pursuant to the type of request submitted." If disclosure is legally permitted, he said, Cricket turns over the data, but "if not, we deny the request."

The information collection is part of the FBI's controversial effort, known internally as "Going Dark," aimed in part at convincing Congress to rewrite federal wiretapping law to require Internet companies including Facebook, Google, Microsoft, and Yahoo to build in back doors for government surveillance. CNET reported in May that the FBI has asked tech companies not to oppose the plan.

Homeland Security's response said its agents had encountered problems when interacting with some mobile and broadband companies -- including Comcast, MetroPCS, and T-Mobile -- though none of the delays or glitches were reported to have derailed a criminal investigation. Other delays appear to be due to disagreements that companies had with Homeland Security's interpretation of the law.

"On a regular basis, the government is unable to obtain communications and related data, even when authorized by a court to do so," the FBI's then-general counsel, Valerie Caproni, told a House of Representatives committee last year.

The request from the FBI's Law Enforcement Executive Forum, a surveillance-focused working group the bureau created in 2001, aims to buttress law enforcement's request for surveillance authority by identifying obstacles posed by current law. It also asks for examples of companies that are not complying with a 1994 law called the Communications Assistance for Law Enforcement Act, or CALEA, which applies to phone companies and broadband providers, but not social-networking Web sites and e-mail and instant messaging providers.

The Homeland Security report, made public this afternoon, was obtained under the Freedom of Information Act by the Electronic Frontier Foundation, which is enmeshed in a lawsuit against the FBI after many of the documents it requested were withheld. CNET reported last week that a federal judge ruled that the government did not adequately respond to EFF's request.

In an unusual twist, Homeland Security provided the partially redacted report (PDF) to the EFF under open government laws -- but then turned around and demanded the document's return, which the EFF refused to do.

A spokesman for the FBI declined to comment on the documents.

In another example from the report, Homeland Security reported that a suspect in an immigration case "was not located" due to SouthernLINC Wireless not permitting agents to access the target's cell phone location in real time because of the request's wording. SouthernLINC, which has about 4.5 million subscribers, would only turn over location data that was one hour old.

That dispute echoes, on a micro scale, a broader dispute about warrantless location tracking that has played out in the courts -- including oral arguments before a federal appeals court last month -- and in the U.S. Congress. James Baker, the associate deputy attorney general, has told Congress that requiring warrants before police could obtain location data from mobile providers would hinder "the government's ability to obtain important information in investigations of serious crimes."

Homeland Security's Honolulu office reported "delays as long as three to four months" in receiving responses to subpoenas sent to T-Mobile and Cricket, and its Phoenix office said that a "significant number" of targets were using Mexican Nextel phones. Homeland Security also complained that Comcast was slow in responding to a "customs summons" because agents asked for "connection records" without specifying Internet Protocol addresses assigned to customers.